27 files changed, 975 insertions, 929 deletions

diff --git a/bench/wtperf/config.c b/bench/wtperf/config.c
index 0dc38287155..475b6ffd2a4 100644
--- a/bench/wtperf/config.c
+++ b/bench/wtperf/config.c
@@ -390,9 +390,9 @@ config_threads(CONFIG *cfg, const char *config, size_t len)
 	return (0);
 
 err:	if (group != NULL)
-		(void)group->close(group);
+		testutil_check(group->close(group));
 	if (scan != NULL)
-		(void)scan->close(scan);
+		testutil_check(scan->close(scan));
 
 	fprintf(stderr,
 	    "invalid thread configuration or scan error: %.*s\n",
diff --git a/bench/wtperf/wtperf.c b/bench/wtperf/wtperf.c
index 58271106d61..12730872c47 100644
--- a/bench/wtperf/wtperf.c
+++ b/bench/wtperf/wtperf.c
@@ -2558,7 +2558,7 @@ drop_all_tables(CONFIG *cfg)
 		    "Error opening a session on %s", cfg->home);
 		return (ret);
 	}
-	(void)__wt_epoch(NULL, &start);
+	testutil_check(__wt_epoch(NULL, &start));
 	for (i = 0; i < cfg->table_count; i++) {
 		if ((ret = session->drop(
 		    session, cfg->uris[i], NULL)) != 0) {
@@ -2567,7 +2567,7 @@ drop_all_tables(CONFIG *cfg)
 			goto err;
 		}
 	}
-	(void)__wt_epoch(NULL, &stop);
+	testutil_check(__wt_epoch(NULL, &stop));
 	msecs = WT_TIMEDIFF_MS(stop, start);
 	lprintf(cfg, 0, 1,
 	    "Executed %" PRIu32 " drop operations average time %" PRIu64 "ms",
diff --git a/bench/wtperf/wtperf_truncate.c b/bench/wtperf/wtperf_truncate.c
index 672b07301e3..e6ebc83c681 100644
--- a/bench/wtperf/wtperf_truncate.c
+++ b/bench/wtperf/wtperf_truncate.c
@@ -192,7 +192,7 @@ run_truncate(CONFIG *cfg, CONFIG_THREAD *thread,
 	 */
 	if (cfg->truncate_single_ops) {
 		while ((ret = cursor->next(cursor)) == 0) {
-			cursor->get_key(cursor, &next_key);
+			testutil_check(cursor->get_key(cursor, &next_key));
 			if (strcmp(next_key, truncate_item->key) == 0)
 				break;
 			if ((ret = cursor->remove(cursor)) != 0) {
diff --git a/dist/s_prototypes b/dist/s_prototypes
index 73f7be371ea..3ca44de07a8 100755
--- a/dist/s_prototypes
+++ b/dist/s_prototypes
@@ -28,7 +28,7 @@ proto()
 	    -e 's/\* /\*/g' \
 	    -e 's/  */ /g' \
 	    -e 's/^/extern /' \
-	    -e 's/WT_GCC_FUNC_/WT_GCC_FUNC_DECL_/g' \
+	    -e 's/WT_GCC_FUNC_ATTRIBUTE/WT_GCC_FUNC_DECL_ATTRIBUTE/g' \
 	    -e '# If a line ends in #endif, appending a semicolon will result' \
 	    -e '# in an illegal expression, force an appended newline using' \
 	    -e '# the H command because substitute may not allow newline in' \
@@ -39,6 +39,9 @@ proto()
 		-e H \
 		-e x \
 	    -e '}' \
+	    -e '# Add the gcc warn_unused_result attribute to any external' \
+	    -e '# functions that return an int.' \
+	    -e '/^extern int /s/$/ WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result))/' \
 	    -e 's/$/;/' \
 	    -e p < $1
 }
diff --git a/dist/s_style b/dist/s_style
index e33db5a5fab..93d04008f0c 100755
--- a/dist/s_style
+++ b/dist/s_style
@@ -173,7 +173,7 @@ else
 	    -e 's/\([	 ,]\)u_int64_t\([	 ,]\)/\1uint64_t\2/g' \
 	    -e 's/\([	 ,]\)u_quad\([	 ,]\)/\1uint64_t\2/g' \
 	    -e 's/\([|&=+-]\)  *\([^*]\)/\1 \2/' \
-	    -e 's/(void) \([a-zA-Z_]\)/(void)\1/' \
+	    -e 's/[	 ](void) \([a-zA-Z_]\)/(void)\1/' \
 	    -e '/for /!s/;;$/;/' \
 	    -e 's/(EOPNOTSUPP)/(ENOTSUP)/' \
 	    -e 's/(unsigned)/(u_int)/' \
diff --git a/examples/c/ex_all.c b/examples/c/ex_all.c
index e8727df3f60..a2042c22bbb 100644
--- a/examples/c/ex_all.c
+++ b/examples/c/ex_all.c
@@ -1126,7 +1126,7 @@ main(void)
 	    home, NULL, "create,file_extend=(data=16MB)", &conn);
 	/*! [Configure file_extend] */
 	if (ret == 0)
-		(void)conn->close(conn, NULL);
+		ret = conn->close(conn, NULL);
 
 	/*! [Eviction configuration] */
 	/*
@@ -1137,7 +1137,7 @@ main(void)
 	    "create,eviction_trigger=90,eviction_dirty_target=75", &conn);
 	/*! [Eviction configuration] */
 	if (ret == 0)
-		(void)conn->close(conn, NULL);
+		ret = conn->close(conn, NULL);
 
 	/*! [Eviction worker configuration] */
 	/* Configure up to four eviction threads */
@@ -1145,20 +1145,20 @@ main(void)
 	    "create,eviction_trigger=90,eviction=(threads_max=4)", &conn);
 	/*! [Eviction worker configuration] */
 	if (ret == 0)
-		(void)conn->close(conn, NULL);
+		ret = conn->close(conn, NULL);
 
 	/*! [Statistics configuration] */
 	ret = wiredtiger_open(home, NULL, "create,statistics=(all)", &conn);
 	/*! [Statistics configuration] */
 	if (ret == 0)
-		(void)conn->close(conn, NULL);
+		ret = conn->close(conn, NULL);
 
 	/*! [Statistics logging] */
 	ret = wiredtiger_open(
 	    home, NULL, "create,statistics_log=(wait=30)", &conn);
 	/*! [Statistics logging] */
 	if (ret == 0)
-		(void)conn->close(conn, NULL);
+		ret = conn->close(conn, NULL);
 
 #ifdef MIGHT_NOT_RUN
 	/*
@@ -1171,7 +1171,7 @@ main(void)
 	    &conn);
 	/*! [Statistics logging with a table] */
 	if (ret == 0)
-		(void)conn->close(conn, NULL);
+		ret = conn->close(conn, NULL);
 
 	/*
 	 * Don't run this code, statistics logging doesn't yet support indexes.
@@ -1182,7 +1182,7 @@ main(void)
 	    &conn);
 	/*! [Statistics logging with a source type] */
 	if (ret == 0)
-		(void)conn->close(conn, NULL);
+		ret = conn->close(conn, NULL);
 
 	/*
 	 * Don't run this code, because memory checkers get very upset when we
diff --git a/ext/encryptors/rotn/rotn_encrypt.c b/ext/encryptors/rotn/rotn_encrypt.c
index 9a92ae7b642..3b5379ca410 100644
--- a/ext/encryptors/rotn/rotn_encrypt.c
+++ b/ext/encryptors/rotn/rotn_encrypt.c
@@ -448,9 +448,10 @@ rotn_configure(ROTN_ENCRYPTOR *rotn_encryptor, WT_CONFIG_ARG *config)
 		    strlen("rotn_force_error") == k.len) {
 			rotn_encryptor->force_error = v.val == 0 ? 0 : 1;
 			continue;
-		}
-		else {
-			(void)config_parser->close(config_parser);
+		} else {
+			if ((ret = config_parser->close(config_parser)) != 0)
+				return (rotn_error(rotn_encryptor,
+				    NULL, ret, "WT_CONFIG_PARSER.close"));
 			return (rotn_error(rotn_encryptor, NULL, EINVAL,
 			    "unknown config key"));
 		}
diff --git a/src/async/async_api.c b/src/async/async_api.c
index d53a6c65c1d..42fe4378d15 100644
--- a/src/async/async_api.c
+++ b/src/async/async_api.c
@@ -89,7 +89,7 @@ setup:	op->format = af;
 
 err:
 	if (c != NULL)
-		(void)c->close(c);
+		WT_TRET(c->close(c));
 	__wt_free(session, af->uri);
 	__wt_free(session, af->config);
 	__wt_free(session, af->key_format);
diff --git a/src/bloom/bloom.c b/src/bloom/bloom.c
index e32544d5521..76b1b5f68ad 100644
--- a/src/bloom/bloom.c
+++ b/src/bloom/bloom.c
@@ -105,7 +105,7 @@ __wt_bloom_create(
 	*bloomp = bloom;
 	return (0);
 
-err:	(void)__wt_bloom_close(bloom);
+err:	WT_TRET(__wt_bloom_close(bloom));
 	return (ret);
 }
 
@@ -166,7 +166,7 @@ __wt_bloom_open(WT_SESSION_IMPL *session,
 	*bloomp = bloom;
 	return (0);
 
-err:	(void)__wt_bloom_close(bloom);
+err:	WT_TRET(__wt_bloom_close(bloom));
 	return (ret);
 }
 
diff --git a/src/btree/bt_debug.c b/src/btree/bt_debug.c
index b1579d25dc6..d4b1362fbfe 100644
--- a/src/btree/bt_debug.c
+++ b/src/btree/bt_debug.c
@@ -12,45 +12,47 @@
 /*
  * We pass around a session handle and output information, group it together.
  */
-typedef struct {
+typedef struct __wt_dbg WT_DBG;
+struct __wt_dbg {
 	WT_SESSION_IMPL *session;		/* Enclosing session */
 
 	/*
 	 * When using the standard event handlers, the debugging output has to
 	 * do its own message handling because its output isn't line-oriented.
 	 */
-	FILE		*fp;
+	FILE		*fp;			/* Optional file handle */
 	WT_ITEM		*msg;			/* Buffered message */
 
+	int (*f)(WT_DBG *, const char *, ...)	/* Function to write */
+	    WT_GCC_FUNC_DECL_ATTRIBUTE((format (printf, 2, 3)));
+
 	WT_ITEM		*tmp;			/* Temporary space */
-} WT_DBG;
+};
 
 static const					/* Output separator */
     char * const sep = "=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=\n";
 
-static int  __debug_cell(WT_DBG *, const WT_PAGE_HEADER *, WT_CELL_UNPACK *);
-static int  __debug_cell_data(
+static int __debug_cell(WT_DBG *, const WT_PAGE_HEADER *, WT_CELL_UNPACK *);
+static int __debug_cell_data(
 	WT_DBG *, WT_PAGE *, int type, const char *, WT_CELL_UNPACK *);
-static void __debug_col_skip(WT_DBG *, WT_INSERT_HEAD *, const char *, bool);
-static int  __debug_config(WT_SESSION_IMPL *, WT_DBG *, const char *);
-static int  __debug_dsk_cell(WT_DBG *, const WT_PAGE_HEADER *);
-static void __debug_dsk_col_fix(WT_DBG *, const WT_PAGE_HEADER *);
-static void __debug_item(WT_DBG *, const char *, const void *, size_t);
-static int  __debug_page(WT_DBG *, WT_REF *, uint32_t);
-static void __debug_page_col_fix(WT_DBG *, WT_REF *);
-static int  __debug_page_col_int(WT_DBG *, WT_PAGE *, uint32_t);
-static int  __debug_page_col_var(WT_DBG *, WT_REF *);
-static int  __debug_page_metadata(WT_DBG *, WT_REF *);
-static int  __debug_page_row_int(WT_DBG *, WT_PAGE *, uint32_t);
-static int  __debug_page_row_leaf(WT_DBG *, WT_PAGE *);
-static void __debug_ref(WT_DBG *, WT_REF *);
-static void __debug_row_skip(WT_DBG *, WT_INSERT_HEAD *);
-static int  __debug_tree(
+static int __debug_col_skip(WT_DBG *, WT_INSERT_HEAD *, const char *, bool);
+static int __debug_config(WT_SESSION_IMPL *, WT_DBG *, const char *);
+static int __debug_dsk_cell(WT_DBG *, const WT_PAGE_HEADER *);
+static int __debug_dsk_col_fix(WT_DBG *, const WT_PAGE_HEADER *);
+static int __debug_item(WT_DBG *, const char *, const void *, size_t);
+static int __debug_page(WT_DBG *, WT_REF *, uint32_t);
+static int __debug_page_col_fix(WT_DBG *, WT_REF *);
+static int __debug_page_col_int(WT_DBG *, WT_PAGE *, uint32_t);
+static int __debug_page_col_var(WT_DBG *, WT_REF *);
+static int __debug_page_metadata(WT_DBG *, WT_REF *);
+static int __debug_page_row_int(WT_DBG *, WT_PAGE *, uint32_t);
+static int __debug_page_row_leaf(WT_DBG *, WT_PAGE *);
+static int __debug_ref(WT_DBG *, WT_REF *);
+static int __debug_row_skip(WT_DBG *, WT_INSERT_HEAD *);
+static int __debug_tree(
 	WT_SESSION_IMPL *, WT_BTREE *, WT_REF *, const char *, uint32_t);
-static void __debug_update(WT_DBG *, WT_UPDATE *, bool);
-static void __dmsg(WT_DBG *, const char *, ...)
-	WT_GCC_FUNC_DECL_ATTRIBUTE((format (printf, 2, 3)));
-static void __dmsg_wrapup(WT_DBG *);
+static int __debug_update(WT_DBG *, WT_UPDATE *, bool);
+static int __dmsg_wrapup(WT_DBG *);
 
 /*
  * __wt_debug_set_verbose --
@@ -71,10 +73,80 @@ __wt_debug_set_verbose(WT_SESSION_IMPL *session, const char *v)
  * __debug_hex_byte --
  *	Output a single byte in hex.
  */
-static inline void
+static inline int
 __debug_hex_byte(WT_DBG *ds, uint8_t v)
 {
-	__dmsg(ds, "#%c%c", __wt_hex[(v & 0xf0) >> 4], __wt_hex[v & 0x0f]);
+	return (ds->f(
+	    ds, "#%c%c", __wt_hex[(v & 0xf0) >> 4], __wt_hex[v & 0x0f]));
+}
+
+/*
+ * __dmsg_event --
+ *	Send a debug message to the event handler.
+ */
+static int
+__dmsg_event(WT_DBG *ds, const char *fmt, ...)
+{
+	WT_ITEM *msg;
+	WT_SESSION_IMPL *session;
+	size_t len, space;
+	va_list ap;
+	char *p;
+
+	session = ds->session;
+
+	/*
+	 * Debug output chunks are not necessarily terminated with a newline
+	 * character.  It's easy if we're dumping to a stream, but if we're
+	 * dumping to an event handler, which is line-oriented, we must buffer
+	 * the output chunk, and pass it to the event handler once we see a
+	 * terminating newline.
+	 */
+	msg = ds->msg;
+	for (;;) {
+		p = (char *)msg->mem + msg->size;
+		space = msg->memsize - msg->size;
+		va_start(ap, fmt);
+		len = (size_t)vsnprintf(p, space, fmt, ap);
+		va_end(ap);
+
+		/* Check if there was enough space. */
+		if (len < space) {
+			msg->size += len;
+			break;
+		}
+
+		/*
+		 * There's not much to do on error without checking for
+		 * an error return on every single printf.  Anyway, it's
+		 * pretty unlikely and this is debugging output, I'm not
+		 * going to worry about it.
+		 */
+		WT_RET(__wt_buf_grow(session, msg, msg->memsize + len + 128));
+	}
+	if (((uint8_t *)msg->mem)[msg->size - 1] == '\n') {
+		((uint8_t *)msg->mem)[msg->size - 1] = '\0';
+		WT_RET(__wt_msg(session, "%s", (char *)msg->mem));
+		msg->size = 0;
+	}
+
+	return (0);
+}
+
+/*
+ * __dmsg_file --
+ *	Send a debug message to a file.
+ */
+static int
+__dmsg_file(WT_DBG *ds, const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	(void)vfprintf(ds->fp, fmt, ap);
+	va_end(ap);
+
+	return (0);
 }
 
 /*
@@ -94,12 +166,15 @@ __debug_config(WT_SESSION_IMPL *session, WT_DBG *ds, const char *ofile)
 	 * If we weren't given a file, we use the default event handler, and
 	 * we'll have to buffer messages.
 	 */
-	if (ofile == NULL)
-		return (__wt_scr_alloc(session, 512, &ds->msg));
-
-	if ((ds->fp = fopen(ofile, "w")) == NULL)
-		return (EIO);
-	__wt_stream_set_line_buffer(ds->fp);
+	if (ofile == NULL) {
+		WT_RET(__wt_scr_alloc(session, 512, &ds->msg));
+		ds->f = __dmsg_event;
+	} else {
+		if ((ds->fp = fopen(ofile, "w")) == NULL)
+			return (EIO);
+		__wt_stream_set_line_buffer(ds->fp);
+		ds->f = __dmsg_file;
+	}
 
 	return (0);
 }
@@ -108,7 +183,7 @@ __debug_config(WT_SESSION_IMPL *session, WT_DBG *ds, const char *ofile)
  * __dmsg_wrapup --
  *	Flush any remaining output, release resources.
  */
-static void
+static int
 __dmsg_wrapup(WT_DBG *ds)
 {
 	WT_SESSION_IMPL *session;
@@ -125,72 +200,15 @@ __dmsg_wrapup(WT_DBG *ds)
 	 */
 	if (msg != NULL) {
 		if (msg->size != 0)
-			(void)__wt_msg(session, "%s", (char *)msg->mem);
+			WT_RET(__wt_msg(session, "%s", (char *)msg->mem));
 		__wt_scr_free(session, &ds->msg);
 	}
 
 	/* Close any file we opened. */
 	if (ds->fp != NULL)
 		(void)fclose(ds->fp);
-}
 
-/*
- * __dmsg --
- *	Debug message.
- */
-static void
-__dmsg(WT_DBG *ds, const char *fmt, ...)
-{
-	va_list ap;
-	WT_ITEM *msg;
-	WT_SESSION_IMPL *session;
-	size_t len, space;
-	char *p;
-
-	session = ds->session;
-
-	/*
-	 * Debug output chunks are not necessarily terminated with a newline
-	 * character.  It's easy if we're dumping to a stream, but if we're
-	 * dumping to an event handler, which is line-oriented, we must buffer
-	 * the output chunk, and pass it to the event handler once we see a
-	 * terminating newline.
-	 */
-	if (ds->fp == NULL) {
-		msg = ds->msg;
-		for (;;) {
-			p = (char *)msg->mem + msg->size;
-			space = msg->memsize - msg->size;
-			va_start(ap, fmt);
-			len = (size_t)vsnprintf(p, space, fmt, ap);
-			va_end(ap);
-
-			/* Check if there was enough space. */
-			if (len < space) {
-				msg->size += len;
-				break;
-			}
-
-			/*
-			 * There's not much to do on error without checking for
-			 * an error return on every single printf.  Anyway, it's
-			 * pretty unlikely and this is debugging output, I'm not
-			 * going to worry about it.
-			 */
-			if (__wt_buf_grow(
-			    session, msg, msg->memsize + len + 128) != 0)
-				return;
-		}
-		if (((uint8_t *)msg->mem)[msg->size - 1] == '\n') {
-			((uint8_t *)msg->mem)[msg->size - 1] = '\0';
-			(void)__wt_msg(session, "%s", (char *)msg->mem);
-			msg->size = 0;
-		}
-	} else {
-		va_start(ap, fmt);
-		(void)vfprintf(ds->fp, fmt, ap);
-		va_end(ap);
-	}
+	return (0);
 }
 
 /*
@@ -314,69 +332,66 @@ __wt_debug_disk(
     WT_SESSION_IMPL *session, const WT_PAGE_HEADER *dsk, const char *ofile)
 {
 	WT_DBG *ds, _ds;
-	WT_DECL_RET;
 
 	ds = &_ds;
 	WT_RET(__debug_config(session, ds, ofile));
 
-	__dmsg(ds, "%s page", __wt_page_type_string(dsk->type));
+	WT_RET(ds->f(ds, "%s page", __wt_page_type_string(dsk->type)));
 	switch (dsk->type) {
 	case WT_PAGE_BLOCK_MANAGER:
 		break;
 	case WT_PAGE_COL_FIX:
 	case WT_PAGE_COL_INT:
 	case WT_PAGE_COL_VAR:
-		__dmsg(ds, ", recno %" PRIu64, dsk->recno);
+		WT_RET(ds->f(ds, ", recno %" PRIu64, dsk->recno));
 		/* FALLTHROUGH */
 	case WT_PAGE_ROW_INT:
 	case WT_PAGE_ROW_LEAF:
-		__dmsg(ds, ", entries %" PRIu32, dsk->u.entries);
+		WT_RET(ds->f(ds, ", entries %" PRIu32, dsk->u.entries));
 		break;
 	case WT_PAGE_OVFL:
-		__dmsg(ds, ", datalen %" PRIu32, dsk->u.datalen);
+		WT_RET(ds->f(ds, ", datalen %" PRIu32, dsk->u.datalen));
 		break;
 	WT_ILLEGAL_VALUE(session);
 	}
 
 	if (F_ISSET(dsk, WT_PAGE_COMPRESSED))
-		__dmsg(ds, ", compressed");
+		WT_RET(ds->f(ds, ", compressed"));
 	if (F_ISSET(dsk, WT_PAGE_ENCRYPTED))
-		__dmsg(ds, ", encrypted");
+		WT_RET(ds->f(ds, ", encrypted"));
 	if (F_ISSET(dsk, WT_PAGE_EMPTY_V_ALL))
-		__dmsg(ds, ", empty-all");
+		WT_RET(ds->f(ds, ", empty-all"));
 	if (F_ISSET(dsk, WT_PAGE_EMPTY_V_NONE))
-		__dmsg(ds, ", empty-none");
+		WT_RET(ds->f(ds, ", empty-none"));
 	if (F_ISSET(dsk, WT_PAGE_LAS_UPDATE))
-		__dmsg(ds, ", LAS-update");
+		WT_RET(ds->f(ds, ", LAS-update"));
 
-	__dmsg(ds, ", generation %" PRIu64 "\n", dsk->write_gen);
+	WT_RET(ds->f(ds, ", generation %" PRIu64 "\n", dsk->write_gen));
 
 	switch (dsk->type) {
 	case WT_PAGE_BLOCK_MANAGER:
 		break;
 	case WT_PAGE_COL_FIX:
-		__debug_dsk_col_fix(ds, dsk);
+		WT_RET(__debug_dsk_col_fix(ds, dsk));
 		break;
 	case WT_PAGE_COL_INT:
 	case WT_PAGE_COL_VAR:
 	case WT_PAGE_ROW_INT:
 	case WT_PAGE_ROW_LEAF:
-		ret = __debug_dsk_cell(ds, dsk);
+		WT_RET(__debug_dsk_cell(ds, dsk));
 		break;
 	default:
 		break;
 	}
 
-	__dmsg_wrapup(ds);
-
-	return (ret);
+	return (__dmsg_wrapup(ds));
 }
 
 /*
  * __debug_dsk_col_fix --
  *	Dump a WT_PAGE_COL_FIX page.
  */
-static void
+static int
 __debug_dsk_col_fix(WT_DBG *ds, const WT_PAGE_HEADER *dsk)
 {
 	WT_BTREE *btree;
@@ -388,10 +403,11 @@ __debug_dsk_col_fix(WT_DBG *ds, const WT_PAGE_HEADER *dsk)
 	btree = S2BT(ds->session);
 
 	WT_FIX_FOREACH(btree, dsk, v, i) {
-		__dmsg(ds, "\t{");
-		__debug_hex_byte(ds, v);
-		__dmsg(ds, "}\n");
+		WT_RET(ds->f(ds, "\t{"));
+		WT_RET(__debug_hex_byte(ds, v));
+		WT_RET(ds->f(ds, "}\n"));
 	}
+	return (0);
 }
 
 /*
@@ -444,7 +460,7 @@ __debug_tree_shape_info(WT_PAGE *page)
  * __debug_tree_shape_worker --
  *	Dump information about the current page and descend.
  */
-static void
+static int
 __debug_tree_shape_worker(WT_DBG *ds, WT_PAGE *page, int level)
 {
 	WT_REF *ref;
@@ -453,16 +469,17 @@ __debug_tree_shape_worker(WT_DBG *ds, WT_PAGE *page, int level)
 	session = ds->session;
 
 	if (WT_PAGE_IS_INTERNAL(page)) {
-		__dmsg(ds, "%*s" "I" "%d %s\n",
-		    level * 3, " ", level, __debug_tree_shape_info(page));
+		WT_RET(ds->f(ds, "%*s" "I" "%d %s\n",
+		    level * 3, " ", level, __debug_tree_shape_info(page)));
 		WT_INTL_FOREACH_BEGIN(session, page, ref) {
 			if (ref->state == WT_REF_MEM)
-				__debug_tree_shape_worker(
-				    ds, ref->page, level + 1);
+				WT_RET(__debug_tree_shape_worker(
+				    ds, ref->page, level + 1));
 		} WT_INTL_FOREACH_END;
 	} else
-		__dmsg(ds, "%*s" "L" " %s\n",
-		    level * 3, " ", __debug_tree_shape_info(page));
+		WT_RET(ds->f(ds, "%*s" "L" " %s\n",
+		    level * 3, " ", __debug_tree_shape_info(page)));
+	return (0);
 }
 
 /*
@@ -474,6 +491,7 @@ __wt_debug_tree_shape(
     WT_SESSION_IMPL *session, WT_PAGE *page, const char *ofile)
 {
 	WT_DBG *ds, _ds;
+	WT_DECL_RET;
 
 	WT_ASSERT(session, S2BT_SAFE(session) != NULL);
 
@@ -484,10 +502,11 @@ __wt_debug_tree_shape(
 	if (page == NULL)
 		page = S2BT(session)->root.page;
 
-	WT_WITH_PAGE_INDEX(session, __debug_tree_shape_worker(ds, page, 1));
+	WT_WITH_PAGE_INDEX(session,
+	    ret = __debug_tree_shape_worker(ds, page, 1));
+	WT_RET(ret);
 
-	__dmsg_wrapup(ds);
-	return (0);
+	return (__dmsg_wrapup(ds));
 }
 
 #define	WT_DEBUG_TREE_LEAF	0x01			/* Debug leaf pages */
@@ -530,18 +549,15 @@ int
 __wt_debug_page(WT_SESSION_IMPL *session, WT_REF *ref, const char *ofile)
 {
 	WT_DBG *ds, _ds;
-	WT_DECL_RET;
 
 	WT_ASSERT(session, S2BT_SAFE(session) != NULL);
 
 	ds = &_ds;
 	WT_RET(__debug_config(session, ds, ofile));
 
-	ret = __debug_page(ds, ref, WT_DEBUG_TREE_LEAF);
-
-	__dmsg_wrapup(ds);
+	WT_RET(__debug_page(ds, ref, WT_DEBUG_TREE_LEAF));
 
-	return (ret);
+	return (__dmsg_wrapup(ds));
 }
 
 /*
@@ -567,10 +583,9 @@ __debug_tree(WT_SESSION_IMPL *session,
 		ref = &btree->root;
 
 	WT_WITH_BTREE(session, btree, ret = __debug_page(ds, ref, flags));
+	WT_RET(ret);
 
-	__dmsg_wrapup(ds);
-
-	return (ret);
+	return (__dmsg_wrapup(ds));
 }
 
 /*
@@ -593,7 +608,7 @@ __debug_page(WT_DBG *ds, WT_REF *ref, uint32_t flags)
 	switch (ref->page->type) {
 	case WT_PAGE_COL_FIX:
 		if (LF_ISSET(WT_DEBUG_TREE_LEAF))
-			__debug_page_col_fix(ds, ref);
+			WT_RET(__debug_page_col_fix(ds, ref));
 		break;
 	case WT_PAGE_COL_INT:
 		WT_WITH_PAGE_INDEX(session,
@@ -636,20 +651,20 @@ __debug_page_metadata(WT_DBG *ds, WT_REF *ref)
 	page = ref->page;
 	mod = page->modify;
 
-	__dmsg(ds, "%p", (void *)page);
+	WT_RET(ds->f(ds, "%p", (void *)page));
 
 	switch (page->type) {
 	case WT_PAGE_COL_INT:
-		__dmsg(ds, " recno %" PRIu64, ref->ref_recno);
+		WT_RET(ds->f(ds, " recno %" PRIu64, ref->ref_recno));
 		WT_INTL_INDEX_GET(session, page, pindex);
 		entries = pindex->entries;
 		break;
 	case WT_PAGE_COL_FIX:
-		__dmsg(ds, " recno %" PRIu64, ref->ref_recno);
+		WT_RET(ds->f(ds, " recno %" PRIu64, ref->ref_recno));
 		entries = page->pg_fix_entries;
 		break;
 	case WT_PAGE_COL_VAR:
-		__dmsg(ds, " recno %" PRIu64, ref->ref_recno);
+		WT_RET(ds->f(ds, " recno %" PRIu64, ref->ref_recno));
 		entries = page->pg_var_entries;
 		break;
 	case WT_PAGE_ROW_INT:
@@ -662,48 +677,50 @@ __debug_page_metadata(WT_DBG *ds, WT_REF *ref)
 	WT_ILLEGAL_VALUE(session);
 	}
 
-	__dmsg(ds, ": %s\n", __wt_page_type_string(page->type));
-	__dmsg(ds,
-	    "\t" "disk %p, entries %" PRIu32, (void *)page->dsk, entries);
-	__dmsg(ds, ", %s", __wt_page_is_modified(page) ? "dirty" : "clean");
-	__dmsg(ds, ", %s", __wt_fair_islocked(
-	    session, &page->page_lock) ? "locked" : "unlocked");
+	WT_RET(ds->f(ds, ": %s\n", __wt_page_type_string(page->type)));
+	WT_RET(ds->f(ds,
+	    "\t" "disk %p, entries %" PRIu32, (void *)page->dsk, entries));
+	WT_RET(ds->f(ds,
+	    ", %s", __wt_page_is_modified(page) ? "dirty" : "clean"));
+	WT_RET(ds->f(ds, ", %s", __wt_fair_islocked(
+	    session, &page->page_lock) ? "locked" : "unlocked"));
 
 	if (F_ISSET_ATOMIC(page, WT_PAGE_BUILD_KEYS))
-		__dmsg(ds, ", keys-built");
+		WT_RET(ds->f(ds, ", keys-built"));
 	if (F_ISSET_ATOMIC(page, WT_PAGE_DISK_ALLOC))
-		__dmsg(ds, ", disk-alloc");
+		WT_RET(ds->f(ds, ", disk-alloc"));
 	if (F_ISSET_ATOMIC(page, WT_PAGE_DISK_MAPPED))
-		__dmsg(ds, ", disk-mapped");
+		WT_RET(ds->f(ds, ", disk-mapped"));
 	if (F_ISSET_ATOMIC(page, WT_PAGE_EVICT_LRU))
-		__dmsg(ds, ", evict-lru");
+		WT_RET(ds->f(ds, ", evict-lru"));
 	if (F_ISSET_ATOMIC(page, WT_PAGE_OVERFLOW_KEYS))
-		__dmsg(ds, ", overflow-keys");
+		WT_RET(ds->f(ds, ", overflow-keys"));
 	if (F_ISSET_ATOMIC(page, WT_PAGE_SPLIT_BLOCK))
-		__dmsg(ds, ", split-block");
+		WT_RET(ds->f(ds, ", split-block"));
 	if (F_ISSET_ATOMIC(page, WT_PAGE_SPLIT_INSERT))
-		__dmsg(ds, ", split-insert");
+		WT_RET(ds->f(ds, ", split-insert"));
 	if (F_ISSET_ATOMIC(page, WT_PAGE_UPDATE_IGNORE))
-		__dmsg(ds, ", update-ignore");
+		WT_RET(ds->f(ds, ", update-ignore"));
 
 	if (mod != NULL)
 		switch (mod->rec_result) {
 		case WT_PM_REC_EMPTY:
-			__dmsg(ds, ", empty");
+			WT_RET(ds->f(ds, ", empty"));
 			break;
 		case WT_PM_REC_MULTIBLOCK:
-			__dmsg(ds, ", multiblock");
+			WT_RET(ds->f(ds, ", multiblock"));
 			break;
 		case WT_PM_REC_REPLACE:
-			__dmsg(ds, ", replaced");
+			WT_RET(ds->f(ds, ", replaced"));
 			break;
 		case 0:
 			break;
 		WT_ILLEGAL_VALUE(session);
 		}
 	if (mod != NULL)
-		__dmsg(ds, ", write generation=%" PRIu32, mod->write_gen);
-	__dmsg(ds, "\n");
+		WT_RET(
+		    ds->f(ds, ", write generation=%" PRIu32, mod->write_gen));
+	WT_RET(ds->f(ds, "\n"));
 
 	return (0);
 }
@@ -712,7 +729,7 @@ __debug_page_metadata(WT_DBG *ds, WT_REF *ref)
  * __debug_page_col_fix --
  *	Dump an in-memory WT_PAGE_COL_FIX page.
  */
-static void
+static int
 __debug_page_col_fix(WT_DBG *ds, WT_REF *ref)
 {
 	WT_BTREE *btree;
@@ -735,16 +752,15 @@ __debug_page_col_fix(WT_DBG *ds, WT_REF *ref)
 	if (dsk != NULL) {
 		ins = WT_SKIP_FIRST(WT_COL_UPDATE_SINGLE(page));
 		WT_FIX_FOREACH(btree, dsk, v, i) {
-			__dmsg(ds, "\t%" PRIu64 "\t{", recno);
-			__debug_hex_byte(ds, v);
-			__dmsg(ds, "}\n");
+			WT_RET(ds->f(ds, "\t%" PRIu64 "\t{", recno));
+			WT_RET(__debug_hex_byte(ds, v));
+			WT_RET(ds->f(ds, "}\n"));
 
 			/* Check for a match on the update list. */
 			if (ins != NULL && WT_INSERT_RECNO(ins) == recno) {
-				__dmsg(ds,
-				    "\tupdate %" PRIu64 "\n",
-				    WT_INSERT_RECNO(ins));
-				__debug_update(ds, ins->upd, true);
+				WT_RET(ds->f(ds, "\tupdate %" PRIu64 "\n",
+				    WT_INSERT_RECNO(ins)));
+				WT_RET(__debug_update(ds, ins->upd, true));
 				ins = WT_SKIP_NEXT(ins);
 			}
 			++recno;
@@ -752,14 +768,16 @@ __debug_page_col_fix(WT_DBG *ds, WT_REF *ref)
 	}
 
 	if (WT_COL_UPDATE_SINGLE(page) != NULL) {
-		__dmsg(ds, "%s", sep);
-		__debug_col_skip(
-		    ds, WT_COL_UPDATE_SINGLE(page), "update", true);
+		WT_RET(ds->f(ds, "%s", sep));
+		WT_RET(__debug_col_skip(
+		    ds, WT_COL_UPDATE_SINGLE(page), "update", true));
 	}
 	if (WT_COL_APPEND(page) != NULL) {
-		__dmsg(ds, "%s", sep);
-		__debug_col_skip(ds, WT_COL_APPEND(page), "append", true);
+		WT_RET(ds->f(ds, "%s", sep));
+		WT_RET(__debug_col_skip(ds,
+		    WT_COL_APPEND(page), "append", true));
 	}
+	return (0);
 }
 
 /*
@@ -775,14 +793,14 @@ __debug_page_col_int(WT_DBG *ds, WT_PAGE *page, uint32_t flags)
 	session = ds->session;
 
 	WT_INTL_FOREACH_BEGIN(session, page, ref) {
-		__dmsg(ds, "\trecno %" PRIu64 "\n", ref->ref_recno);
-		__debug_ref(ds, ref);
+		WT_RET(ds->f(ds, "\trecno %" PRIu64 "\n", ref->ref_recno));
+		WT_RET(__debug_ref(ds, ref));
 	} WT_INTL_FOREACH_END;
 
 	if (LF_ISSET(WT_DEBUG_TREE_WALK))
 		WT_INTL_FOREACH_BEGIN(session, page, ref) {
 			if (ref->state == WT_REF_MEM) {
-				__dmsg(ds, "\n");
+				WT_RET(ds->f(ds, "\n"));
 				WT_RET(__debug_page(ds, ref, flags));
 			}
 		} WT_INTL_FOREACH_END;
@@ -823,13 +841,14 @@ __debug_page_col_var(WT_DBG *ds, WT_REF *ref)
 		    __debug_cell_data(ds, page, WT_PAGE_COL_VAR, tag, unpack));
 
 		if ((update = WT_COL_UPDATE(page, cip)) != NULL)
-			__debug_col_skip(ds, update, "update", false);
+			WT_RET(__debug_col_skip(ds, update, "update", false));
 		recno += rle;
 	}
 
 	if (WT_COL_APPEND(page) != NULL) {
-		__dmsg(ds, "%s", sep);
-		__debug_col_skip(ds, WT_COL_APPEND(page), "append", false);
+		WT_RET(ds->f(ds, "%s", sep));
+		WT_RET(__debug_col_skip(ds,
+		    WT_COL_APPEND(page), "append", false));
 	}
 
 	return (0);
@@ -851,14 +870,14 @@ __debug_page_row_int(WT_DBG *ds, WT_PAGE *page, uint32_t flags)
 
 	WT_INTL_FOREACH_BEGIN(session, page, ref) {
 		__wt_ref_key(page, ref, &p, &len);
-		__debug_item(ds, "K", p, len);
-		__debug_ref(ds, ref);
+		WT_RET(__debug_item(ds, "K", p, len));
+		WT_RET(__debug_ref(ds, ref));
 	} WT_INTL_FOREACH_END;
 
 	if (LF_ISSET(WT_DEBUG_TREE_WALK))
 		WT_INTL_FOREACH_BEGIN(session, page, ref) {
 			if (ref->state == WT_REF_MEM) {
-				__dmsg(ds, "\n");
+				WT_RET(ds->f(ds, "\n"));
 				WT_RET(__debug_page(ds, ref, flags));
 			}
 		} WT_INTL_FOREACH_END;
@@ -891,15 +910,15 @@ __debug_page_row_leaf(WT_DBG *ds, WT_PAGE *page)
 	 * key on the page.
 	 */
 	if ((insert = WT_ROW_INSERT_SMALLEST(page)) != NULL)
-		__debug_row_skip(ds, insert);
+		WT_ERR(__debug_row_skip(ds, insert));
 
 	/* Dump the page's K/V pairs. */
 	WT_ROW_FOREACH(page, rip, i) {
 		WT_ERR(__wt_row_leaf_key(session, page, rip, key, false));
-		__debug_item(ds, "K", key->data, key->size);
+		WT_ERR(__debug_item(ds, "K", key->data, key->size));
 
 		if ((cell = __wt_row_leaf_value_cell(page, rip, NULL)) == NULL)
-			__dmsg(ds, "\tV {}\n");
+			WT_ERR(ds->f(ds, "\tV {}\n"));
 		else {
 			__wt_cell_unpack(cell, unpack);
 			WT_ERR(__debug_cell_data(
@@ -907,10 +926,10 @@ __debug_page_row_leaf(WT_DBG *ds, WT_PAGE *page)
 		}
 
 		if ((upd = WT_ROW_UPDATE(page, rip)) != NULL)
-			__debug_update(ds, upd, false);
+			WT_ERR(__debug_update(ds, upd, false));
 
 		if ((insert = WT_ROW_INSERT(page, rip)) != NULL)
-			__debug_row_skip(ds, insert);
+			WT_ERR(__debug_row_skip(ds, insert));
 	}
 
 err:	__wt_scr_free(session, &key);
@@ -921,59 +940,63 @@ err:	__wt_scr_free(session, &key);
  * __debug_col_skip --
  *	Dump a column-store skiplist.
  */
-static void
+static int
 __debug_col_skip(
     WT_DBG *ds, WT_INSERT_HEAD *head, const char *tag, bool hexbyte)
 {
 	WT_INSERT *ins;
 
 	WT_SKIP_FOREACH(ins, head) {
-		__dmsg(ds,
-		    "\t%s %" PRIu64 "\n", tag, WT_INSERT_RECNO(ins));
-		__debug_update(ds, ins->upd, hexbyte);
+		WT_RET(ds->f(ds,
+		    "\t%s %" PRIu64 "\n", tag, WT_INSERT_RECNO(ins)));
+		WT_RET(__debug_update(ds, ins->upd, hexbyte));
 	}
+	return (0);
 }
 
 /*
  * __debug_row_skip --
  *	Dump an insert list.
  */
-static void
+static int
 __debug_row_skip(WT_DBG *ds, WT_INSERT_HEAD *head)
 {
 	WT_INSERT *ins;
 
 	WT_SKIP_FOREACH(ins, head) {
-		__debug_item(ds,
-		    "insert", WT_INSERT_KEY(ins), WT_INSERT_KEY_SIZE(ins));
-		__debug_update(ds, ins->upd, false);
+		WT_RET(__debug_item(ds,
+		    "insert", WT_INSERT_KEY(ins), WT_INSERT_KEY_SIZE(ins)));
+		WT_RET(__debug_update(ds, ins->upd, false));
 	}
+	return (0);
 }
 
 /*
  * __debug_update --
  *	Dump an update list.
  */
-static void
+static int
 __debug_update(WT_DBG *ds, WT_UPDATE *upd, bool hexbyte)
 {
 	for (; upd != NULL; upd = upd->next)
 		if (WT_UPDATE_DELETED_ISSET(upd))
-			__dmsg(ds, "\tvalue {deleted}\n");
+			WT_RET(ds->f(ds, "\tvalue {deleted}\n"));
 		else if (hexbyte) {
-			__dmsg(ds, "\t{");
-			__debug_hex_byte(ds, *(uint8_t *)WT_UPDATE_DATA(upd));
-			__dmsg(ds, "}\n");
+			WT_RET(ds->f(ds, "\t{"));
+			WT_RET(__debug_hex_byte(ds,
+			    *(uint8_t *)WT_UPDATE_DATA(upd)));
+			WT_RET(ds->f(ds, "}\n"));
 		} else
-			__debug_item(ds,
-			    "value", WT_UPDATE_DATA(upd), upd->size);
+			WT_RET(__debug_item(ds,
+			    "value", WT_UPDATE_DATA(upd), upd->size));
+	return (0);
 }
 
 /*
  * __debug_ref --
  *	Dump a WT_REF structure.
  */
-static void
+static int
 __debug_ref(WT_DBG *ds, WT_REF *ref)
 {
 	WT_SESSION_IMPL *session;
@@ -982,34 +1005,34 @@ __debug_ref(WT_DBG *ds, WT_REF *ref)
 
 	session = ds->session;
 
-	__dmsg(ds, "\t");
+	WT_RET(ds->f(ds, "\t"));
 	switch (ref->state) {
 	case WT_REF_DISK:
-		__dmsg(ds, "disk");
+		WT_RET(ds->f(ds, "disk"));
 		break;
 	case WT_REF_DELETED:
-		__dmsg(ds, "deleted");
+		WT_RET(ds->f(ds, "deleted"));
 		break;
 	case WT_REF_LOCKED:
-		__dmsg(ds, "locked %p", (void *)ref->page);
+		WT_RET(ds->f(ds, "locked %p", (void *)ref->page));
 		break;
 	case WT_REF_MEM:
-		__dmsg(ds, "memory %p", (void *)ref->page);
+		WT_RET(ds->f(ds, "memory %p", (void *)ref->page));
 		break;
 	case WT_REF_READING:
-		__dmsg(ds, "reading");
+		WT_RET(ds->f(ds, "reading"));
 		break;
 	case WT_REF_SPLIT:
-		__dmsg(ds, "split");
+		WT_RET(ds->f(ds, "split"));
 		break;
 	default:
-		__dmsg(ds, "INVALID");
+		WT_RET(ds->f(ds, "INVALID"));
 		break;
 	}
 
 	__wt_ref_info(ref, &addr, &addr_size, NULL);
-	__dmsg(ds, " %s\n",
-	    __wt_addr_string(session, addr, addr_size, ds->tmp));
+	return (ds->f(ds, " %s\n",
+	    __wt_addr_string(session, addr, addr_size, ds->tmp)));
 }
 
 /*
@@ -1026,15 +1049,15 @@ __debug_cell(WT_DBG *ds, const WT_PAGE_HEADER *dsk, WT_CELL_UNPACK *unpack)
 
 	session = ds->session;
 
-	__dmsg(ds, "\t%s: len %" PRIu32,
-	    __wt_cell_type_string(unpack->raw), unpack->size);
+	WT_RET(ds->f(ds, "\t%s: len %" PRIu32,
+	    __wt_cell_type_string(unpack->raw), unpack->size));
 
 	/* Dump cell's per-disk page type information. */
 	switch (dsk->type) {
 	case WT_PAGE_COL_INT:
 		switch (unpack->type) {
 		case WT_CELL_VALUE:
-			__dmsg(ds, ", recno: %" PRIu64, unpack->v);
+			WT_RET(ds->f(ds, ", recno: %" PRIu64, unpack->v));
 			break;
 		}
 		break;
@@ -1045,7 +1068,8 @@ __debug_cell(WT_DBG *ds, const WT_PAGE_HEADER *dsk, WT_CELL_UNPACK *unpack)
 		case WT_CELL_VALUE:
 		case WT_CELL_VALUE_OVFL:
 		case WT_CELL_VALUE_OVFL_RM:
-			__dmsg(ds, ", rle: %" PRIu64, __wt_cell_rle(unpack));
+			WT_RET(ds->f(ds,
+			    ", rle: %" PRIu64, __wt_cell_rle(unpack)));
 			break;
 		}
 		break;
@@ -1053,7 +1077,7 @@ __debug_cell(WT_DBG *ds, const WT_PAGE_HEADER *dsk, WT_CELL_UNPACK *unpack)
 	case WT_PAGE_ROW_LEAF:
 		switch (unpack->type) {
 		case WT_CELL_KEY:
-			__dmsg(ds, ", pfx: %" PRIu8, unpack->prefix);
+			WT_RET(ds->f(ds, ", pfx: %" PRIu8, unpack->prefix));
 			break;
 		}
 		break;
@@ -1079,13 +1103,14 @@ __debug_cell(WT_DBG *ds, const WT_PAGE_HEADER *dsk, WT_CELL_UNPACK *unpack)
 	case WT_CELL_VALUE_OVFL_RM:
 		type = "ovfl";
 addr:		WT_RET(__wt_scr_alloc(session, 128, &buf));
-		__dmsg(ds, ", %s %s", type,
-		    __wt_addr_string(session, unpack->data, unpack->size, buf));
+		WT_RET(ds->f(ds, ", %s %s", type,
+		    __wt_addr_string(
+		    session, unpack->data, unpack->size, buf)));
 		__wt_scr_free(session, &buf);
 		WT_RET(ret);
 		break;
 	}
-	__dmsg(ds, "\n");
+	WT_RET(ds->f(ds, "\n"));
 
 	return (__debug_cell_data(ds, NULL, dsk->type, NULL, unpack));
 }
@@ -1110,7 +1135,7 @@ __debug_cell_data(WT_DBG *ds,
 	 * reference.
 	 */
 	if (unpack == NULL) {
-		__debug_item(ds, tag, "deleted", strlen("deleted"));
+		WT_RET(__debug_item(ds, tag, "deleted", strlen("deleted")));
 		return (0);
 	}
 
@@ -1123,7 +1148,7 @@ __debug_cell_data(WT_DBG *ds,
 	case WT_CELL_KEY_OVFL_RM:
 	case WT_CELL_VALUE_OVFL_RM:
 		p = __wt_cell_type_string(unpack->raw);
-		__debug_item(ds, tag, p, strlen(p));
+		WT_RET(__debug_item(ds, tag, p, strlen(p)));
 		break;
 	case WT_CELL_KEY:
 	case WT_CELL_KEY_OVFL:
@@ -1139,7 +1164,7 @@ __debug_cell_data(WT_DBG *ds,
 		    __wt_dsk_cell_data_ref(session, page_type, unpack, buf) :
 		    __wt_page_cell_data_ref(session, page, unpack, buf);
 		if (ret == 0)
-			__debug_item(ds, tag, buf->data, buf->size);
+			WT_RET(__debug_item(ds, tag, buf->data, buf->size));
 		__wt_scr_free(session, &buf);
 		break;
 	WT_ILLEGAL_VALUE(session);
@@ -1152,21 +1177,23 @@ __debug_cell_data(WT_DBG *ds,
  * __debug_item --
  *	Dump a single data/size pair, with an optional tag.
  */
-static void
+static int
 __debug_item(WT_DBG *ds, const char *tag, const void *data_arg, size_t size)
 {
 	size_t i;
 	u_char ch;
 	const uint8_t *data;
 
-	__dmsg(ds, "\t%s%s{", tag == NULL ? "" : tag, tag == NULL ? "" : " ");
+	WT_RET(ds->f(ds,
+	    "\t%s%s{", tag == NULL ? "" : tag, tag == NULL ? "" : " "));
 	for (data = data_arg, i = 0; i < size; ++i, ++data) {
 		ch = data[0];
 		if (__wt_isprint(ch))
-			__dmsg(ds, "%c", (int)ch);
+			WT_RET(ds->f(ds, "%c", (int)ch));
 		else
-			__debug_hex_byte(ds, data[0]);
+			WT_RET(__debug_hex_byte(ds, data[0]));
 	}
-	__dmsg(ds, "}\n");
+	WT_RET(ds->f(ds, "}\n"));
+	return (0);
 }
 #endif
diff --git a/src/btree/bt_read.c b/src/btree/bt_read.c
index 3d396d5ae5b..f052ba77b6f 100644
--- a/src/btree/bt_read.c
+++ b/src/btree/bt_read.c
@@ -323,10 +323,10 @@ __evict_force_check(WT_SESSION_IMPL *session, WT_REF *ref)
 		return (__wt_leaf_page_can_split(session, page));
 
 	/* Trigger eviction on the next page release. */
-	(void)__wt_page_evict_soon(session, ref);
+	WT_IGNORE_RET(__wt_page_evict_soon(session, ref));
 
 	/* Bump the oldest ID, we're about to do some visibility checks. */
-	(void)__wt_txn_update_oldest(session, 0);
+	WT_IGNORE_RET(__wt_txn_update_oldest(session, 0));
 
 	/* If eviction cannot succeed, don't try. */
 	return (__wt_page_can_evict(session, ref, NULL));
@@ -605,8 +605,8 @@ __wt_page_in_func(WT_SESSION_IMPL *session, WT_REF *ref, uint32_t flags
 					 * are holding a hazard pointer to the
 					 * page already.
 					 */
-					(void)__wt_page_evict_soon(
-					    session, ref);
+					WT_IGNORE_RET(
+					    __wt_page_evict_soon(session, ref));
 				else
 					__wt_cache_read_gen_new(session, page);
 			} else if (!LF_ISSET(WT_READ_NO_GEN))
diff --git a/src/cursor/cur_std.c b/src/cursor/cur_std.c
index 8bb8931f36f..86594179907 100644
--- a/src/cursor/cur_std.c
+++ b/src/cursor/cur_std.c
@@ -50,7 +50,7 @@ __wt_cursor_get_value_notsup(WT_CURSOR *cursor, ...)
 void
 __wt_cursor_set_key_notsup(WT_CURSOR *cursor, ...)
 {
-	(void)__wt_cursor_notsup(cursor);
+	WT_IGNORE_RET(__wt_cursor_notsup(cursor));
 }
 
 /*
@@ -60,7 +60,7 @@ __wt_cursor_set_key_notsup(WT_CURSOR *cursor, ...)
 void
 __wt_cursor_set_value_notsup(WT_CURSOR *cursor, ...)
 {
-	(void)__wt_cursor_notsup(cursor);
+	WT_IGNORE_RET(__wt_cursor_notsup(cursor));
 }
 
 /*
diff --git a/src/evict/evict_lru.c b/src/evict/evict_lru.c
index f677f2d9458..929e36f039d 100644
--- a/src/evict/evict_lru.c
+++ b/src/evict/evict_lru.c
@@ -306,10 +306,11 @@ __evict_server(WT_SESSION_IMPL *session, bool *did_work)
 		/* After being stuck for 5 minutes, give up. */
 		WT_RET(__wt_epoch(session, &now));
 		if (WT_TIMEDIFF_SEC(now, cache->stuck_ts) > 300) {
-			__wt_err(session, ETIMEDOUT,
+			ret = ETIMEDOUT;
+			__wt_err(session, ret,
 			    "Cache stuck for too long, giving up");
-			(void)__wt_cache_dump(session, NULL);
-			WT_RET(ETIMEDOUT);
+			WT_TRET(__wt_cache_dump(session, NULL));
+			return (ret);
 		}
 #endif
 	}
diff --git a/src/include/error.h b/src/include/error.h
index 5f24d205af9..e85220d5d3c 100644
--- a/src/include/error.h
+++ b/src/include/error.h
@@ -95,10 +95,11 @@
 
 #define	WT_PANIC_MSG(session, v, ...) do {				\
 	__wt_err(session, v, __VA_ARGS__);				\
-	(void)__wt_panic(session);					\
+	WT_IGNORE_RET(__wt_panic(session));				\
 } while (0)
 #define	WT_PANIC_ERR(session, v, ...) do {				\
 	WT_PANIC_MSG(session, v, __VA_ARGS__);				\
+	/* Return WT_PANIC regardless of earlier return codes. */	\
 	WT_ERR(WT_PANIC);						\
 } while (0)
 #define	WT_PANIC_RET(session, v, ...) do {				\
diff --git a/src/include/extern.h b/src/include/extern.h
index f3a639ac07f..5a12a7f333a 100644
--- a/src/include/extern.h
+++ b/src/include/extern.h
@@ -1,641 +1,642 @@
 /* DO NOT EDIT: automatically built by dist/s_prototypes. */
 
 extern void __wt_async_stats_update(WT_SESSION_IMPL *session);
-extern int __wt_async_create(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_async_reconfig(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_async_destroy(WT_SESSION_IMPL *session);
-extern int __wt_async_flush(WT_SESSION_IMPL *session);
-extern int __wt_async_new_op(WT_SESSION_IMPL *session, const char *uri, const char *config, const char *cfg[], WT_ASYNC_CALLBACK *cb, WT_ASYNC_OP_IMPL **opp);
-extern int __wt_async_op_enqueue(WT_SESSION_IMPL *session, WT_ASYNC_OP_IMPL *op);
-extern int __wt_async_op_init(WT_SESSION_IMPL *session);
+extern int __wt_async_create(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_async_reconfig(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_async_destroy(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_async_flush(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_async_new_op(WT_SESSION_IMPL *session, const char *uri, const char *config, const char *cfg[], WT_ASYNC_CALLBACK *cb, WT_ASYNC_OP_IMPL **opp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_async_op_enqueue(WT_SESSION_IMPL *session, WT_ASYNC_OP_IMPL *op) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_async_op_init(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern WT_THREAD_RET __wt_async_worker(void *arg);
-extern int __wt_block_addr_to_buffer(WT_BLOCK *block, uint8_t **pp, wt_off_t offset, uint32_t size, uint32_t cksum);
-extern int __wt_block_buffer_to_addr(WT_BLOCK *block, const uint8_t *p, wt_off_t *offsetp, uint32_t *sizep, uint32_t *cksump);
-extern int __wt_block_addr_invalid(WT_SESSION_IMPL *session, WT_BLOCK *block, const uint8_t *addr, size_t addr_size, bool live);
-extern int __wt_block_addr_string(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_ITEM *buf, const uint8_t *addr, size_t addr_size);
-extern int __wt_block_buffer_to_ckpt(WT_SESSION_IMPL *session, WT_BLOCK *block, const uint8_t *p, WT_BLOCK_CKPT *ci);
-extern int __wt_block_ckpt_decode(WT_SESSION *wt_session, size_t allocsize, const uint8_t *p, WT_BLOCK_CKPT *ci);
-extern int __wt_block_ckpt_to_buffer(WT_SESSION_IMPL *session, WT_BLOCK *block, uint8_t **pp, WT_BLOCK_CKPT *ci);
-extern int __wt_block_ckpt_init( WT_SESSION_IMPL *session, WT_BLOCK_CKPT *ci, const char *name);
-extern int __wt_block_checkpoint_load(WT_SESSION_IMPL *session, WT_BLOCK *block, const uint8_t *addr, size_t addr_size, uint8_t *root_addr, size_t *root_addr_sizep, bool checkpoint);
-extern int __wt_block_checkpoint_unload( WT_SESSION_IMPL *session, WT_BLOCK *block, bool checkpoint);
+extern int __wt_block_addr_to_buffer(WT_BLOCK *block, uint8_t **pp, wt_off_t offset, uint32_t size, uint32_t cksum) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_buffer_to_addr(WT_BLOCK *block, const uint8_t *p, wt_off_t *offsetp, uint32_t *sizep, uint32_t *cksump) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_addr_invalid(WT_SESSION_IMPL *session, WT_BLOCK *block, const uint8_t *addr, size_t addr_size, bool live) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_addr_string(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_ITEM *buf, const uint8_t *addr, size_t addr_size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_buffer_to_ckpt(WT_SESSION_IMPL *session, WT_BLOCK *block, const uint8_t *p, WT_BLOCK_CKPT *ci) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_ckpt_decode(WT_SESSION *wt_session, size_t allocsize, const uint8_t *p, WT_BLOCK_CKPT *ci) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_ckpt_to_buffer(WT_SESSION_IMPL *session, WT_BLOCK *block, uint8_t **pp, WT_BLOCK_CKPT *ci) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_ckpt_init( WT_SESSION_IMPL *session, WT_BLOCK_CKPT *ci, const char *name) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_checkpoint_load(WT_SESSION_IMPL *session, WT_BLOCK *block, const uint8_t *addr, size_t addr_size, uint8_t *root_addr, size_t *root_addr_sizep, bool checkpoint) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_checkpoint_unload( WT_SESSION_IMPL *session, WT_BLOCK *block, bool checkpoint) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_block_ckpt_destroy(WT_SESSION_IMPL *session, WT_BLOCK_CKPT *ci);
-extern int __wt_block_checkpoint(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_ITEM *buf, WT_CKPT *ckptbase, bool data_cksum);
-extern int __wt_block_checkpoint_resolve(WT_SESSION_IMPL *session, WT_BLOCK *block);
-extern int __wt_block_compact_start(WT_SESSION_IMPL *session, WT_BLOCK *block);
-extern int __wt_block_compact_end(WT_SESSION_IMPL *session, WT_BLOCK *block);
-extern int __wt_block_compact_skip(WT_SESSION_IMPL *session, WT_BLOCK *block, bool *skipp);
-extern int __wt_block_compact_page_skip(WT_SESSION_IMPL *session, WT_BLOCK *block, const uint8_t *addr, size_t addr_size, bool *skipp);
-extern int __wt_block_misplaced(WT_SESSION_IMPL *session, WT_BLOCK *block, const char *tag, wt_off_t offset, uint32_t size, bool live);
-extern int __wt_block_off_remove_overlap(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_EXTLIST *el, wt_off_t off, wt_off_t size);
-extern int __wt_block_alloc( WT_SESSION_IMPL *session, WT_BLOCK *block, wt_off_t *offp, wt_off_t size);
-extern int __wt_block_free(WT_SESSION_IMPL *session, WT_BLOCK *block, const uint8_t *addr, size_t addr_size);
-extern int __wt_block_off_free( WT_SESSION_IMPL *session, WT_BLOCK *block, wt_off_t offset, wt_off_t size);
-extern int __wt_block_extlist_check( WT_SESSION_IMPL *session, WT_EXTLIST *al, WT_EXTLIST *bl);
-extern int __wt_block_extlist_overlap( WT_SESSION_IMPL *session, WT_BLOCK *block, WT_BLOCK_CKPT *ci);
-extern int __wt_block_extlist_merge(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_EXTLIST *a, WT_EXTLIST *b);
-extern int __wt_block_insert_ext(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_EXTLIST *el, wt_off_t off, wt_off_t size);
-extern int __wt_block_extlist_read_avail(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_EXTLIST *el, wt_off_t ckpt_size);
-extern int __wt_block_extlist_read(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_EXTLIST *el, wt_off_t ckpt_size);
-extern int __wt_block_extlist_write(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_EXTLIST *el, WT_EXTLIST *additional);
-extern int __wt_block_extlist_truncate( WT_SESSION_IMPL *session, WT_BLOCK *block, WT_EXTLIST *el);
-extern int __wt_block_extlist_init(WT_SESSION_IMPL *session, WT_EXTLIST *el, const char *name, const char *extname, bool track_size);
+extern int __wt_block_checkpoint(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_ITEM *buf, WT_CKPT *ckptbase, bool data_cksum) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_checkpoint_resolve(WT_SESSION_IMPL *session, WT_BLOCK *block) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_compact_start(WT_SESSION_IMPL *session, WT_BLOCK *block) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_compact_end(WT_SESSION_IMPL *session, WT_BLOCK *block) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_compact_skip(WT_SESSION_IMPL *session, WT_BLOCK *block, bool *skipp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_compact_page_skip(WT_SESSION_IMPL *session, WT_BLOCK *block, const uint8_t *addr, size_t addr_size, bool *skipp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_misplaced(WT_SESSION_IMPL *session, WT_BLOCK *block, const char *tag, wt_off_t offset, uint32_t size, bool live) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_off_remove_overlap(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_EXTLIST *el, wt_off_t off, wt_off_t size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_alloc( WT_SESSION_IMPL *session, WT_BLOCK *block, wt_off_t *offp, wt_off_t size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_free(WT_SESSION_IMPL *session, WT_BLOCK *block, const uint8_t *addr, size_t addr_size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_off_free( WT_SESSION_IMPL *session, WT_BLOCK *block, wt_off_t offset, wt_off_t size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_extlist_check( WT_SESSION_IMPL *session, WT_EXTLIST *al, WT_EXTLIST *bl) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_extlist_overlap( WT_SESSION_IMPL *session, WT_BLOCK *block, WT_BLOCK_CKPT *ci) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_extlist_merge(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_EXTLIST *a, WT_EXTLIST *b) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_insert_ext(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_EXTLIST *el, wt_off_t off, wt_off_t size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_extlist_read_avail(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_EXTLIST *el, wt_off_t ckpt_size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_extlist_read(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_EXTLIST *el, wt_off_t ckpt_size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_extlist_write(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_EXTLIST *el, WT_EXTLIST *additional) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_extlist_truncate( WT_SESSION_IMPL *session, WT_BLOCK *block, WT_EXTLIST *el) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_extlist_init(WT_SESSION_IMPL *session, WT_EXTLIST *el, const char *name, const char *extname, bool track_size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_block_extlist_free(WT_SESSION_IMPL *session, WT_EXTLIST *el);
-extern int __wt_block_map(WT_SESSION_IMPL *session, WT_BLOCK *block, void *mapped_regionp, size_t *lengthp, void *mapped_cookiep);
-extern int __wt_block_unmap(WT_SESSION_IMPL *session, WT_BLOCK *block, void *mapped_region, size_t length, void *mapped_cookie);
-extern int __wt_block_manager_open(WT_SESSION_IMPL *session, const char *filename, const char *cfg[], bool forced_salvage, bool readonly, uint32_t allocsize, WT_BM **bmp);
-extern int __wt_block_manager_drop( WT_SESSION_IMPL *session, const char *filename, bool durable);
-extern int __wt_block_manager_create( WT_SESSION_IMPL *session, const char *filename, uint32_t allocsize);
+extern int __wt_block_map(WT_SESSION_IMPL *session, WT_BLOCK *block, void *mapped_regionp, size_t *lengthp, void *mapped_cookiep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_unmap(WT_SESSION_IMPL *session, WT_BLOCK *block, void *mapped_region, size_t length, void *mapped_cookie) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_manager_open(WT_SESSION_IMPL *session, const char *filename, const char *cfg[], bool forced_salvage, bool readonly, uint32_t allocsize, WT_BM **bmp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_manager_drop( WT_SESSION_IMPL *session, const char *filename, bool durable) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_manager_create( WT_SESSION_IMPL *session, const char *filename, uint32_t allocsize) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_block_configure_first_fit(WT_BLOCK *block, bool on);
-extern int __wt_block_open(WT_SESSION_IMPL *session, const char *filename, const char *cfg[], bool forced_salvage, bool readonly, uint32_t allocsize, WT_BLOCK **blockp);
-extern int __wt_block_close(WT_SESSION_IMPL *session, WT_BLOCK *block);
-extern int __wt_desc_write(WT_SESSION_IMPL *session, WT_FH *fh, uint32_t allocsize);
+extern int __wt_block_open(WT_SESSION_IMPL *session, const char *filename, const char *cfg[], bool forced_salvage, bool readonly, uint32_t allocsize, WT_BLOCK **blockp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_close(WT_SESSION_IMPL *session, WT_BLOCK *block) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_desc_write(WT_SESSION_IMPL *session, WT_FH *fh, uint32_t allocsize) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_block_stat(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_DSRC_STATS *stats);
-extern int __wt_block_manager_size(WT_BM *bm, WT_SESSION_IMPL *session, wt_off_t *sizep);
-extern int __wt_block_manager_named_size( WT_SESSION_IMPL *session, const char *name, wt_off_t *sizep);
-extern int __wt_bm_preload( WT_BM *bm, WT_SESSION_IMPL *session, const uint8_t *addr, size_t addr_size);
-extern int __wt_bm_read(WT_BM *bm, WT_SESSION_IMPL *session, WT_ITEM *buf, const uint8_t *addr, size_t addr_size);
-extern int __wt_block_read_off_blind( WT_SESSION_IMPL *session, WT_BLOCK *block, WT_ITEM *buf, wt_off_t offset);
-extern int __wt_block_read_off(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_ITEM *buf, wt_off_t offset, uint32_t size, uint32_t cksum);
-extern int __wt_block_ext_alloc(WT_SESSION_IMPL *session, WT_EXT **extp);
+extern int __wt_block_manager_size(WT_BM *bm, WT_SESSION_IMPL *session, wt_off_t *sizep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_manager_named_size( WT_SESSION_IMPL *session, const char *name, wt_off_t *sizep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_bm_preload( WT_BM *bm, WT_SESSION_IMPL *session, const uint8_t *addr, size_t addr_size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_bm_read(WT_BM *bm, WT_SESSION_IMPL *session, WT_ITEM *buf, const uint8_t *addr, size_t addr_size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_read_off_blind( WT_SESSION_IMPL *session, WT_BLOCK *block, WT_ITEM *buf, wt_off_t offset) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_read_off(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_ITEM *buf, wt_off_t offset, uint32_t size, uint32_t cksum) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_ext_alloc(WT_SESSION_IMPL *session, WT_EXT **extp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_block_ext_free(WT_SESSION_IMPL *session, WT_EXT *ext);
-extern int __wt_block_size_alloc(WT_SESSION_IMPL *session, WT_SIZE **szp);
+extern int __wt_block_size_alloc(WT_SESSION_IMPL *session, WT_SIZE **szp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_block_size_free(WT_SESSION_IMPL *session, WT_SIZE *sz);
-extern int __wt_block_ext_prealloc(WT_SESSION_IMPL *session, u_int max);
-extern int __wt_block_ext_discard(WT_SESSION_IMPL *session, u_int max);
-extern int __wt_block_salvage_start(WT_SESSION_IMPL *session, WT_BLOCK *block);
-extern int __wt_block_salvage_end(WT_SESSION_IMPL *session, WT_BLOCK *block);
+extern int __wt_block_ext_prealloc(WT_SESSION_IMPL *session, u_int max) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_ext_discard(WT_SESSION_IMPL *session, u_int max) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_salvage_start(WT_SESSION_IMPL *session, WT_BLOCK *block) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_salvage_end(WT_SESSION_IMPL *session, WT_BLOCK *block) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern bool __wt_block_offset_invalid(WT_BLOCK *block, wt_off_t offset, uint32_t size);
-extern int __wt_block_salvage_next(WT_SESSION_IMPL *session, WT_BLOCK *block, uint8_t *addr, size_t *addr_sizep, bool *eofp);
-extern int __wt_block_salvage_valid(WT_SESSION_IMPL *session, WT_BLOCK *block, uint8_t *addr, size_t addr_size, bool valid);
-extern int __wt_block_verify_start(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_CKPT *ckptbase, const char *cfg[]);
-extern int __wt_block_verify_end(WT_SESSION_IMPL *session, WT_BLOCK *block);
-extern int __wt_verify_ckpt_load( WT_SESSION_IMPL *session, WT_BLOCK *block, WT_BLOCK_CKPT *ci);
-extern int __wt_verify_ckpt_unload(WT_SESSION_IMPL *session, WT_BLOCK *block);
-extern int __wt_block_verify_addr(WT_SESSION_IMPL *session, WT_BLOCK *block, const uint8_t *addr, size_t addr_size);
-extern int __wt_block_truncate(WT_SESSION_IMPL *session, WT_BLOCK *block, wt_off_t len);
-extern int __wt_block_discard(WT_SESSION_IMPL *session, WT_BLOCK *block, size_t added_size);
-extern int __wt_block_write_size(WT_SESSION_IMPL *session, WT_BLOCK *block, size_t *sizep);
-extern int __wt_block_write(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_ITEM *buf, uint8_t *addr, size_t *addr_sizep, bool data_cksum, bool checkpoint_io);
-extern int __wt_block_write_off(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_ITEM *buf, wt_off_t *offsetp, uint32_t *sizep, uint32_t *cksump, bool data_cksum, bool checkpoint_io, bool caller_locked);
-extern int __wt_bloom_create( WT_SESSION_IMPL *session, const char *uri, const char *config, uint64_t count, uint32_t factor, uint32_t k, WT_BLOOM **bloomp);
-extern int __wt_bloom_open(WT_SESSION_IMPL *session, const char *uri, uint32_t factor, uint32_t k, WT_CURSOR *owner, WT_BLOOM **bloomp);
-extern int __wt_bloom_insert(WT_BLOOM *bloom, WT_ITEM *key);
-extern int __wt_bloom_finalize(WT_BLOOM *bloom);
-extern int __wt_bloom_hash(WT_BLOOM *bloom, WT_ITEM *key, WT_BLOOM_HASH *bhash);
-extern int __wt_bloom_hash_get(WT_BLOOM *bloom, WT_BLOOM_HASH *bhash);
-extern int __wt_bloom_get(WT_BLOOM *bloom, WT_ITEM *key);
-extern int __wt_bloom_inmem_get(WT_BLOOM *bloom, WT_ITEM *key);
-extern int __wt_bloom_intersection(WT_BLOOM *bloom, WT_BLOOM *other);
-extern int __wt_bloom_close(WT_BLOOM *bloom);
-extern int __wt_bloom_drop(WT_BLOOM *bloom, const char *config);
-extern int __wt_compact(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_compact_page_skip(WT_SESSION_IMPL *session, WT_REF *ref, bool *skipp);
-extern int __wt_cursor_key_order_check( WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt, bool next);
-extern int __wt_cursor_key_order_init(WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt);
+extern int __wt_block_salvage_next(WT_SESSION_IMPL *session, WT_BLOCK *block, uint8_t *addr, size_t *addr_sizep, bool *eofp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_salvage_valid(WT_SESSION_IMPL *session, WT_BLOCK *block, uint8_t *addr, size_t addr_size, bool valid) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_verify_start(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_CKPT *ckptbase, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_verify_end(WT_SESSION_IMPL *session, WT_BLOCK *block) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_verify_ckpt_load( WT_SESSION_IMPL *session, WT_BLOCK *block, WT_BLOCK_CKPT *ci) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_verify_ckpt_unload(WT_SESSION_IMPL *session, WT_BLOCK *block) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_verify_addr(WT_SESSION_IMPL *session, WT_BLOCK *block, const uint8_t *addr, size_t addr_size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_truncate(WT_SESSION_IMPL *session, WT_BLOCK *block, wt_off_t len) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_discard(WT_SESSION_IMPL *session, WT_BLOCK *block, size_t added_size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_write_size(WT_SESSION_IMPL *session, WT_BLOCK *block, size_t *sizep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_write(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_ITEM *buf, uint8_t *addr, size_t *addr_sizep, bool data_cksum, bool checkpoint_io) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_block_write_off(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_ITEM *buf, wt_off_t *offsetp, uint32_t *sizep, uint32_t *cksump, bool data_cksum, bool checkpoint_io, bool caller_locked) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_bloom_create( WT_SESSION_IMPL *session, const char *uri, const char *config, uint64_t count, uint32_t factor, uint32_t k, WT_BLOOM **bloomp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_bloom_open(WT_SESSION_IMPL *session, const char *uri, uint32_t factor, uint32_t k, WT_CURSOR *owner, WT_BLOOM **bloomp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_bloom_insert(WT_BLOOM *bloom, WT_ITEM *key) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_bloom_finalize(WT_BLOOM *bloom) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_bloom_hash(WT_BLOOM *bloom, WT_ITEM *key, WT_BLOOM_HASH *bhash) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_bloom_hash_get(WT_BLOOM *bloom, WT_BLOOM_HASH *bhash) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_bloom_get(WT_BLOOM *bloom, WT_ITEM *key) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_bloom_inmem_get(WT_BLOOM *bloom, WT_ITEM *key) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_bloom_intersection(WT_BLOOM *bloom, WT_BLOOM *other) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_bloom_close(WT_BLOOM *bloom) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_bloom_drop(WT_BLOOM *bloom, const char *config) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_compact(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_compact_page_skip(WT_SESSION_IMPL *session, WT_REF *ref, bool *skipp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cursor_key_order_check( WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt, bool next) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cursor_key_order_init(WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_cursor_key_order_reset(WT_CURSOR_BTREE *cbt);
 extern void __wt_btcur_iterate_setup(WT_CURSOR_BTREE *cbt);
-extern int __wt_btcur_next(WT_CURSOR_BTREE *cbt, bool truncating);
-extern int __wt_btcur_prev(WT_CURSOR_BTREE *cbt, bool truncating);
-extern int __wt_btcur_reset(WT_CURSOR_BTREE *cbt);
-extern int __wt_btcur_search(WT_CURSOR_BTREE *cbt);
-extern int __wt_btcur_search_near(WT_CURSOR_BTREE *cbt, int *exactp);
-extern int __wt_btcur_insert(WT_CURSOR_BTREE *cbt);
-extern int __wt_btcur_update_check(WT_CURSOR_BTREE *cbt);
-extern int __wt_btcur_remove(WT_CURSOR_BTREE *cbt);
-extern int __wt_btcur_update(WT_CURSOR_BTREE *cbt);
-extern int __wt_btcur_next_random(WT_CURSOR_BTREE *cbt);
-extern int __wt_btcur_compare(WT_CURSOR_BTREE *a_arg, WT_CURSOR_BTREE *b_arg, int *cmpp);
-extern int __wt_btcur_equals(WT_CURSOR_BTREE *a_arg, WT_CURSOR_BTREE *b_arg, int *equalp);
-extern int __wt_btcur_range_truncate(WT_CURSOR_BTREE *start, WT_CURSOR_BTREE *stop);
+extern int __wt_btcur_next(WT_CURSOR_BTREE *cbt, bool truncating) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_btcur_prev(WT_CURSOR_BTREE *cbt, bool truncating) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_btcur_reset(WT_CURSOR_BTREE *cbt) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_btcur_search(WT_CURSOR_BTREE *cbt) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_btcur_search_near(WT_CURSOR_BTREE *cbt, int *exactp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_btcur_insert(WT_CURSOR_BTREE *cbt) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_btcur_update_check(WT_CURSOR_BTREE *cbt) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_btcur_remove(WT_CURSOR_BTREE *cbt) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_btcur_update(WT_CURSOR_BTREE *cbt) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_btcur_next_random(WT_CURSOR_BTREE *cbt) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_btcur_compare(WT_CURSOR_BTREE *a_arg, WT_CURSOR_BTREE *b_arg, int *cmpp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_btcur_equals(WT_CURSOR_BTREE *a_arg, WT_CURSOR_BTREE *b_arg, int *equalp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_btcur_range_truncate(WT_CURSOR_BTREE *start, WT_CURSOR_BTREE *stop) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_btcur_init(WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt);
 extern void __wt_btcur_open(WT_CURSOR_BTREE *cbt);
-extern int __wt_btcur_close(WT_CURSOR_BTREE *cbt, bool lowlevel);
-extern int __wt_debug_set_verbose(WT_SESSION_IMPL *session, const char *v);
-extern int __wt_debug_addr_print( WT_SESSION_IMPL *session, const uint8_t *addr, size_t addr_size);
-extern int __wt_debug_addr(WT_SESSION_IMPL *session, const uint8_t *addr, size_t addr_size, const char *ofile);
-extern int __wt_debug_offset_blind( WT_SESSION_IMPL *session, wt_off_t offset, const char *ofile);
-extern int __wt_debug_offset(WT_SESSION_IMPL *session, wt_off_t offset, uint32_t size, uint32_t cksum, const char *ofile);
-extern int __wt_debug_disk( WT_SESSION_IMPL *session, const WT_PAGE_HEADER *dsk, const char *ofile);
-extern int __wt_debug_tree_shape( WT_SESSION_IMPL *session, WT_PAGE *page, const char *ofile);
-extern int __wt_debug_tree_all( WT_SESSION_IMPL *session, WT_BTREE *btree, WT_REF *ref, const char *ofile);
-extern int __wt_debug_tree( WT_SESSION_IMPL *session, WT_BTREE *btree, WT_REF *ref, const char *ofile);
-extern int __wt_debug_page(WT_SESSION_IMPL *session, WT_REF *ref, const char *ofile);
-extern int __wt_delete_page(WT_SESSION_IMPL *session, WT_REF *ref, bool *skipp);
+extern int __wt_btcur_close(WT_CURSOR_BTREE *cbt, bool lowlevel) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_debug_set_verbose(WT_SESSION_IMPL *session, const char *v) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_debug_addr_print( WT_SESSION_IMPL *session, const uint8_t *addr, size_t addr_size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_debug_addr(WT_SESSION_IMPL *session, const uint8_t *addr, size_t addr_size, const char *ofile) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_debug_offset_blind( WT_SESSION_IMPL *session, wt_off_t offset, const char *ofile) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_debug_offset(WT_SESSION_IMPL *session, wt_off_t offset, uint32_t size, uint32_t cksum, const char *ofile) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_debug_disk( WT_SESSION_IMPL *session, const WT_PAGE_HEADER *dsk, const char *ofile) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_debug_tree_shape( WT_SESSION_IMPL *session, WT_PAGE *page, const char *ofile) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_debug_tree_all( WT_SESSION_IMPL *session, WT_BTREE *btree, WT_REF *ref, const char *ofile) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_debug_tree( WT_SESSION_IMPL *session, WT_BTREE *btree, WT_REF *ref, const char *ofile) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_debug_page(WT_SESSION_IMPL *session, WT_REF *ref, const char *ofile) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_delete_page(WT_SESSION_IMPL *session, WT_REF *ref, bool *skipp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_delete_page_rollback(WT_SESSION_IMPL *session, WT_REF *ref);
 extern bool __wt_delete_page_skip(WT_SESSION_IMPL *session, WT_REF *ref, bool visible_all);
-extern int __wt_delete_page_instantiate(WT_SESSION_IMPL *session, WT_REF *ref);
+extern int __wt_delete_page_instantiate(WT_SESSION_IMPL *session, WT_REF *ref) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_ref_out(WT_SESSION_IMPL *session, WT_REF *ref);
 extern void __wt_page_out(WT_SESSION_IMPL *session, WT_PAGE **pagep);
 extern void __wt_free_ref( WT_SESSION_IMPL *session, WT_REF *ref, int page_type, bool free_pages);
 extern void __wt_free_ref_index(WT_SESSION_IMPL *session, WT_PAGE *page, WT_PAGE_INDEX *pindex, bool free_pages);
 extern void __wt_free_update_list(WT_SESSION_IMPL *session, WT_UPDATE *upd);
-extern int __wt_btree_open(WT_SESSION_IMPL *session, const char *op_cfg[]);
-extern int __wt_btree_close(WT_SESSION_IMPL *session);
+extern int __wt_btree_open(WT_SESSION_IMPL *session, const char *op_cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_btree_close(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_root_ref_init(WT_REF *root_ref, WT_PAGE *root, bool is_recno);
-extern int __wt_btree_tree_open( WT_SESSION_IMPL *session, const uint8_t *addr, size_t addr_size);
-extern int __wt_btree_new_leaf_page(WT_SESSION_IMPL *session, WT_PAGE **pagep);
+extern int __wt_btree_tree_open( WT_SESSION_IMPL *session, const uint8_t *addr, size_t addr_size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_btree_new_leaf_page(WT_SESSION_IMPL *session, WT_PAGE **pagep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_btree_evictable(WT_SESSION_IMPL *session, bool on);
-extern int __wt_btree_huffman_open(WT_SESSION_IMPL *session);
+extern int __wt_btree_huffman_open(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_btree_huffman_close(WT_SESSION_IMPL *session);
-extern int __wt_bt_read(WT_SESSION_IMPL *session, WT_ITEM *buf, const uint8_t *addr, size_t addr_size);
-extern int __wt_bt_write(WT_SESSION_IMPL *session, WT_ITEM *buf, uint8_t *addr, size_t *addr_sizep, bool checkpoint, bool checkpoint_io, bool compressed);
+extern int __wt_bt_read(WT_SESSION_IMPL *session, WT_ITEM *buf, const uint8_t *addr, size_t addr_size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_bt_write(WT_SESSION_IMPL *session, WT_ITEM *buf, uint8_t *addr, size_t *addr_sizep, bool checkpoint, bool checkpoint_io, bool compressed) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern const char *__wt_page_type_string(u_int type);
 extern const char *__wt_cell_type_string(uint8_t type);
 extern const char *__wt_page_addr_string(WT_SESSION_IMPL *session, WT_REF *ref, WT_ITEM *buf);
 extern const char *__wt_addr_string(WT_SESSION_IMPL *session, const uint8_t *addr, size_t addr_size, WT_ITEM *buf);
-extern int __wt_ovfl_read(WT_SESSION_IMPL *session, WT_PAGE *page, WT_CELL_UNPACK *unpack, WT_ITEM *store);
-extern int __wt_ovfl_cache(WT_SESSION_IMPL *session, WT_PAGE *page, void *cookie, WT_CELL_UNPACK *vpack);
-extern int __wt_ovfl_discard(WT_SESSION_IMPL *session, WT_CELL *cell);
-extern int __wt_page_alloc(WT_SESSION_IMPL *session, uint8_t type, uint32_t alloc_entries, bool alloc_refs, WT_PAGE **pagep);
-extern int __wt_page_inmem(WT_SESSION_IMPL *session, WT_REF *ref, const void *image, size_t memsize, uint32_t flags, WT_PAGE **pagep);
-extern int __wt_las_remove_block(WT_SESSION_IMPL *session, WT_CURSOR *cursor, uint32_t btree_id, const uint8_t *addr, size_t addr_size);
+extern int __wt_ovfl_read(WT_SESSION_IMPL *session, WT_PAGE *page, WT_CELL_UNPACK *unpack, WT_ITEM *store) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ovfl_cache(WT_SESSION_IMPL *session, WT_PAGE *page, void *cookie, WT_CELL_UNPACK *vpack) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ovfl_discard(WT_SESSION_IMPL *session, WT_CELL *cell) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_page_alloc(WT_SESSION_IMPL *session, uint8_t type, uint32_t alloc_entries, bool alloc_refs, WT_PAGE **pagep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_page_inmem(WT_SESSION_IMPL *session, WT_REF *ref, const void *image, size_t memsize, uint32_t flags, WT_PAGE **pagep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_las_remove_block(WT_SESSION_IMPL *session, WT_CURSOR *cursor, uint32_t btree_id, const uint8_t *addr, size_t addr_size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern int
 __wt_page_in_func(WT_SESSION_IMPL *session, WT_REF *ref, uint32_t flags
 #ifdef HAVE_DIAGNOSTIC
  , const char *file, int line
 #endif
  );
-extern int __wt_bt_rebalance(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_kv_return(WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt, WT_UPDATE *upd);
-extern int __wt_bt_salvage(WT_SESSION_IMPL *session, WT_CKPT *ckptbase, const char *cfg[]);
+extern int __wt_bt_rebalance(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_kv_return(WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt, WT_UPDATE *upd) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_bt_salvage(WT_SESSION_IMPL *session, WT_CKPT *ckptbase, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_split_stash_discard(WT_SESSION_IMPL *session);
 extern void __wt_split_stash_discard_all( WT_SESSION_IMPL *session_safe, WT_SESSION_IMPL *session);
-extern int __wt_multi_to_ref(WT_SESSION_IMPL *session, WT_PAGE *page, WT_MULTI *multi, WT_REF **refp, size_t *incrp, bool closing);
-extern int __wt_split_insert(WT_SESSION_IMPL *session, WT_REF *ref);
-extern int __wt_split_multi(WT_SESSION_IMPL *session, WT_REF *ref, int closing);
-extern int __wt_split_reverse(WT_SESSION_IMPL *session, WT_REF *ref);
-extern int __wt_split_rewrite(WT_SESSION_IMPL *session, WT_REF *ref, WT_MULTI *multi);
-extern int __wt_btree_stat_init(WT_SESSION_IMPL *session, WT_CURSOR_STAT *cst);
-extern int __wt_cache_op(WT_SESSION_IMPL *session, WT_CACHE_OP op);
-extern int __wt_upgrade(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_verify(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_verify_dsk_image(WT_SESSION_IMPL *session, const char *tag, const WT_PAGE_HEADER *dsk, size_t size, bool empty_page_ok);
-extern int __wt_verify_dsk(WT_SESSION_IMPL *session, const char *tag, WT_ITEM *buf);
-extern int __wt_tree_walk(WT_SESSION_IMPL *session, WT_REF **refp, uint32_t flags);
-extern int __wt_tree_walk_count(WT_SESSION_IMPL *session, WT_REF **refp, uint64_t *walkcntp, uint32_t flags);
-extern int __wt_tree_walk_skip(WT_SESSION_IMPL *session, WT_REF **refp, uint64_t *skipleafcntp, uint32_t flags);
-extern int __wt_col_modify(WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt, uint64_t recno, WT_ITEM *value, WT_UPDATE *upd_arg, bool is_remove);
-extern int __wt_col_search(WT_SESSION_IMPL *session, uint64_t search_recno, WT_REF *leaf, WT_CURSOR_BTREE *cbt);
-extern int __wt_row_leaf_keys(WT_SESSION_IMPL *session, WT_PAGE *page);
-extern int __wt_row_leaf_key_copy( WT_SESSION_IMPL *session, WT_PAGE *page, WT_ROW *rip, WT_ITEM *key);
-extern int __wt_row_leaf_key_work(WT_SESSION_IMPL *session, WT_PAGE *page, WT_ROW *rip_arg, WT_ITEM *keyb, bool instantiate);
-extern int __wt_row_ikey_alloc(WT_SESSION_IMPL *session, uint32_t cell_offset, const void *key, size_t size, WT_IKEY **ikeyp);
-extern int __wt_row_ikey_incr(WT_SESSION_IMPL *session, WT_PAGE *page, uint32_t cell_offset, const void *key, size_t size, WT_REF *ref);
-extern int __wt_row_ikey(WT_SESSION_IMPL *session, uint32_t cell_offset, const void *key, size_t size, WT_REF *ref);
-extern int __wt_page_modify_alloc(WT_SESSION_IMPL *session, WT_PAGE *page);
-extern int __wt_row_modify(WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt, WT_ITEM *key, WT_ITEM *value, WT_UPDATE *upd_arg, bool is_remove);
-extern int __wt_row_insert_alloc(WT_SESSION_IMPL *session, WT_ITEM *key, u_int skipdepth, WT_INSERT **insp, size_t *ins_sizep);
-extern int __wt_update_alloc( WT_SESSION_IMPL *session, WT_ITEM *value, WT_UPDATE **updp, size_t *sizep);
+extern int __wt_multi_to_ref(WT_SESSION_IMPL *session, WT_PAGE *page, WT_MULTI *multi, WT_REF **refp, size_t *incrp, bool closing) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_split_insert(WT_SESSION_IMPL *session, WT_REF *ref) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_split_multi(WT_SESSION_IMPL *session, WT_REF *ref, int closing) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_split_reverse(WT_SESSION_IMPL *session, WT_REF *ref) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_split_rewrite(WT_SESSION_IMPL *session, WT_REF *ref, WT_MULTI *multi) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_btree_stat_init(WT_SESSION_IMPL *session, WT_CURSOR_STAT *cst) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cache_op(WT_SESSION_IMPL *session, WT_CACHE_OP op) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_upgrade(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_verify(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_verify_dsk_image(WT_SESSION_IMPL *session, const char *tag, const WT_PAGE_HEADER *dsk, size_t size, bool empty_page_ok) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_verify_dsk(WT_SESSION_IMPL *session, const char *tag, WT_ITEM *buf) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_tree_walk(WT_SESSION_IMPL *session, WT_REF **refp, uint32_t flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_tree_walk_count(WT_SESSION_IMPL *session, WT_REF **refp, uint64_t *walkcntp, uint32_t flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_tree_walk_skip(WT_SESSION_IMPL *session, WT_REF **refp, uint64_t *skipleafcntp, uint32_t flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_col_modify(WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt, uint64_t recno, WT_ITEM *value, WT_UPDATE *upd_arg, bool is_remove) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_col_search(WT_SESSION_IMPL *session, uint64_t search_recno, WT_REF *leaf, WT_CURSOR_BTREE *cbt) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_row_leaf_keys(WT_SESSION_IMPL *session, WT_PAGE *page) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_row_leaf_key_copy( WT_SESSION_IMPL *session, WT_PAGE *page, WT_ROW *rip, WT_ITEM *key) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_row_leaf_key_work(WT_SESSION_IMPL *session, WT_PAGE *page, WT_ROW *rip_arg, WT_ITEM *keyb, bool instantiate) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_row_ikey_alloc(WT_SESSION_IMPL *session, uint32_t cell_offset, const void *key, size_t size, WT_IKEY **ikeyp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_row_ikey_incr(WT_SESSION_IMPL *session, WT_PAGE *page, uint32_t cell_offset, const void *key, size_t size, WT_REF *ref) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_row_ikey(WT_SESSION_IMPL *session, uint32_t cell_offset, const void *key, size_t size, WT_REF *ref) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_page_modify_alloc(WT_SESSION_IMPL *session, WT_PAGE *page) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_row_modify(WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt, WT_ITEM *key, WT_ITEM *value, WT_UPDATE *upd_arg, bool is_remove) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_row_insert_alloc(WT_SESSION_IMPL *session, WT_ITEM *key, u_int skipdepth, WT_INSERT **insp, size_t *ins_sizep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_update_alloc( WT_SESSION_IMPL *session, WT_ITEM *value, WT_UPDATE **updp, size_t *sizep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern WT_UPDATE *__wt_update_obsolete_check( WT_SESSION_IMPL *session, WT_PAGE *page, WT_UPDATE *upd);
 extern void __wt_update_obsolete_free( WT_SESSION_IMPL *session, WT_PAGE *page, WT_UPDATE *upd);
-extern int __wt_search_insert(WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt, WT_INSERT_HEAD *ins_head, WT_ITEM *srch_key);
-extern int __wt_row_search(WT_SESSION_IMPL *session, WT_ITEM *srch_key, WT_REF *leaf, WT_CURSOR_BTREE *cbt, bool insert);
-extern int __wt_row_random_leaf(WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt);
-extern int __wt_row_random_descent(WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt);
+extern int __wt_search_insert(WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt, WT_INSERT_HEAD *ins_head, WT_ITEM *srch_key) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_row_search(WT_SESSION_IMPL *session, WT_ITEM *srch_key, WT_REF *leaf, WT_CURSOR_BTREE *cbt, bool insert) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_row_random_leaf(WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_row_random_descent(WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_las_stats_update(WT_SESSION_IMPL *session);
-extern int __wt_las_create(WT_SESSION_IMPL *session);
-extern int __wt_las_destroy(WT_SESSION_IMPL *session);
+extern int __wt_las_create(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_las_destroy(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_las_set_written(WT_SESSION_IMPL *session);
 extern bool __wt_las_is_written(WT_SESSION_IMPL *session);
-extern int __wt_las_cursor_open(WT_SESSION_IMPL *session, WT_CURSOR **cursorp);
-extern int __wt_las_cursor( WT_SESSION_IMPL *session, WT_CURSOR **cursorp, uint32_t *session_flags);
-extern int __wt_las_cursor_close( 	WT_SESSION_IMPL *session, WT_CURSOR **cursorp, uint32_t session_flags);
-extern int __wt_las_sweep(WT_SESSION_IMPL *session);
+extern int __wt_las_cursor_open(WT_SESSION_IMPL *session, WT_CURSOR **cursorp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_las_cursor( WT_SESSION_IMPL *session, WT_CURSOR **cursorp, uint32_t *session_flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_las_cursor_close( 	WT_SESSION_IMPL *session, WT_CURSOR **cursorp, uint32_t session_flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_las_sweep(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern uint32_t __wt_cksum(const void *chunk, size_t len);
 extern void __wt_cksum_init(void);
-extern int __wt_config_initn( WT_SESSION_IMPL *session, WT_CONFIG *conf, const char *str, size_t len);
-extern int __wt_config_init(WT_SESSION_IMPL *session, WT_CONFIG *conf, const char *str);
-extern int __wt_config_subinit( WT_SESSION_IMPL *session, WT_CONFIG *conf, WT_CONFIG_ITEM *item);
-extern int __wt_config_next(WT_CONFIG *conf, WT_CONFIG_ITEM *key, WT_CONFIG_ITEM *value);
-extern int __wt_config_get(WT_SESSION_IMPL *session, const char **cfg_arg, WT_CONFIG_ITEM *key, WT_CONFIG_ITEM *value);
-extern int __wt_config_gets(WT_SESSION_IMPL *session, const char **cfg, const char *key, WT_CONFIG_ITEM *value);
-extern int __wt_config_gets_none(WT_SESSION_IMPL *session, const char **cfg, const char *key, WT_CONFIG_ITEM *value);
-extern int __wt_config_getone(WT_SESSION_IMPL *session, const char *config, WT_CONFIG_ITEM *key, WT_CONFIG_ITEM *value);
-extern int __wt_config_getones(WT_SESSION_IMPL *session, const char *config, const char *key, WT_CONFIG_ITEM *value);
-extern int __wt_config_getones_none(WT_SESSION_IMPL *session, const char *config, const char *key, WT_CONFIG_ITEM *value);
-extern int __wt_config_gets_def(WT_SESSION_IMPL *session, const char **cfg, const char *key, int def, WT_CONFIG_ITEM *value);
-extern int __wt_config_subgetraw(WT_SESSION_IMPL *session, WT_CONFIG_ITEM *cfg, WT_CONFIG_ITEM *key, WT_CONFIG_ITEM *value);
-extern int __wt_config_subgets(WT_SESSION_IMPL *session, WT_CONFIG_ITEM *cfg, const char *key, WT_CONFIG_ITEM *value);
+extern int __wt_config_initn( WT_SESSION_IMPL *session, WT_CONFIG *conf, const char *str, size_t len) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_config_init(WT_SESSION_IMPL *session, WT_CONFIG *conf, const char *str) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_config_subinit( WT_SESSION_IMPL *session, WT_CONFIG *conf, WT_CONFIG_ITEM *item) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_config_next(WT_CONFIG *conf, WT_CONFIG_ITEM *key, WT_CONFIG_ITEM *value) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_config_get(WT_SESSION_IMPL *session, const char **cfg_arg, WT_CONFIG_ITEM *key, WT_CONFIG_ITEM *value) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_config_gets(WT_SESSION_IMPL *session, const char **cfg, const char *key, WT_CONFIG_ITEM *value) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_config_gets_none(WT_SESSION_IMPL *session, const char **cfg, const char *key, WT_CONFIG_ITEM *value) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_config_getone(WT_SESSION_IMPL *session, const char *config, WT_CONFIG_ITEM *key, WT_CONFIG_ITEM *value) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_config_getones(WT_SESSION_IMPL *session, const char *config, const char *key, WT_CONFIG_ITEM *value) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_config_getones_none(WT_SESSION_IMPL *session, const char *config, const char *key, WT_CONFIG_ITEM *value) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_config_gets_def(WT_SESSION_IMPL *session, const char **cfg, const char *key, int def, WT_CONFIG_ITEM *value) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_config_subgetraw(WT_SESSION_IMPL *session, WT_CONFIG_ITEM *cfg, WT_CONFIG_ITEM *key, WT_CONFIG_ITEM *value) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_config_subgets(WT_SESSION_IMPL *session, WT_CONFIG_ITEM *cfg, const char *key, WT_CONFIG_ITEM *value) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_conn_foc_discard(WT_SESSION_IMPL *session);
-extern int __wt_configure_method(WT_SESSION_IMPL *session, const char *method, const char *uri, const char *config, const char *type, const char *check);
-extern int __wt_config_check(WT_SESSION_IMPL *session, const WT_CONFIG_ENTRY *entry, const char *config, size_t config_len);
-extern int __wt_config_collapse( WT_SESSION_IMPL *session, const char **cfg, char **config_ret);
-extern int __wt_config_merge(WT_SESSION_IMPL *session, const char **cfg, const char *cfg_strip, const char **config_ret);
-extern int __wt_conn_config_init(WT_SESSION_IMPL *session);
+extern int __wt_configure_method(WT_SESSION_IMPL *session, const char *method, const char *uri, const char *config, const char *type, const char *check) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_config_check(WT_SESSION_IMPL *session, const WT_CONFIG_ENTRY *entry, const char *config, size_t config_len) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_config_collapse( WT_SESSION_IMPL *session, const char **cfg, char **config_ret) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_config_merge(WT_SESSION_IMPL *session, const char **cfg, const char *cfg_strip, const char **config_ret) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_conn_config_init(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_conn_config_discard(WT_SESSION_IMPL *session);
 extern const WT_CONFIG_ENTRY *__wt_conn_config_match(const char *method);
-extern int __wt_ext_config_parser_open(WT_EXTENSION_API *wt_ext, WT_SESSION *wt_session, const char *config, size_t len, WT_CONFIG_PARSER **config_parserp);
-extern int __wt_ext_config_get(WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, WT_CONFIG_ARG *cfg_arg, const char *key, WT_CONFIG_ITEM *cval);
-extern int __wt_config_upgrade(WT_SESSION_IMPL *session, WT_ITEM *buf);
+extern int __wt_ext_config_parser_open(WT_EXTENSION_API *wt_ext, WT_SESSION *wt_session, const char *config, size_t len, WT_CONFIG_PARSER **config_parserp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ext_config_get(WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, WT_CONFIG_ARG *cfg_arg, const char *key, WT_CONFIG_ITEM *cval) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_config_upgrade(WT_SESSION_IMPL *session, WT_ITEM *buf) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern const char *__wt_wiredtiger_error(int error);
-extern int __wt_collator_config(WT_SESSION_IMPL *session, const char *uri, WT_CONFIG_ITEM *cname, WT_CONFIG_ITEM *metadata, WT_COLLATOR **collatorp, int *ownp);
-extern int __wt_conn_remove_collator(WT_SESSION_IMPL *session);
-extern int __wt_compressor_config( WT_SESSION_IMPL *session, WT_CONFIG_ITEM *cval, WT_COMPRESSOR **compressorp);
-extern int __wt_conn_remove_compressor(WT_SESSION_IMPL *session);
-extern int __wt_conn_remove_data_source(WT_SESSION_IMPL *session);
-extern int __wt_encryptor_config(WT_SESSION_IMPL *session, WT_CONFIG_ITEM *cval, WT_CONFIG_ITEM *keyid, WT_CONFIG_ARG *cfg_arg, WT_KEYED_ENCRYPTOR **kencryptorp);
-extern int __wt_conn_remove_encryptor(WT_SESSION_IMPL *session);
-extern int __wt_extractor_config(WT_SESSION_IMPL *session, const char *uri, const char *config, WT_EXTRACTOR **extractorp, int *ownp);
-extern int __wt_conn_remove_extractor(WT_SESSION_IMPL *session);
-extern int __wt_verbose_config(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_cache_config(WT_SESSION_IMPL *session, bool reconfigure, const char *cfg[]);
-extern int __wt_cache_create(WT_SESSION_IMPL *session, const char *cfg[]);
+extern int __wt_collator_config(WT_SESSION_IMPL *session, const char *uri, WT_CONFIG_ITEM *cname, WT_CONFIG_ITEM *metadata, WT_COLLATOR **collatorp, int *ownp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_conn_remove_collator(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_compressor_config( WT_SESSION_IMPL *session, WT_CONFIG_ITEM *cval, WT_COMPRESSOR **compressorp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_conn_remove_compressor(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_conn_remove_data_source(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_encryptor_config(WT_SESSION_IMPL *session, WT_CONFIG_ITEM *cval, WT_CONFIG_ITEM *keyid, WT_CONFIG_ARG *cfg_arg, WT_KEYED_ENCRYPTOR **kencryptorp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_conn_remove_encryptor(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_extractor_config(WT_SESSION_IMPL *session, const char *uri, const char *config, WT_EXTRACTOR **extractorp, int *ownp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_conn_remove_extractor(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_verbose_config(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cache_config(WT_SESSION_IMPL *session, bool reconfigure, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cache_create(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_cache_stats_update(WT_SESSION_IMPL *session);
-extern int __wt_cache_destroy(WT_SESSION_IMPL *session);
-extern int __wt_cache_pool_config(WT_SESSION_IMPL *session, const char **cfg);
-extern int __wt_conn_cache_pool_open(WT_SESSION_IMPL *session);
-extern int __wt_conn_cache_pool_destroy(WT_SESSION_IMPL *session);
+extern int __wt_cache_destroy(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cache_pool_config(WT_SESSION_IMPL *session, const char **cfg) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_conn_cache_pool_open(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_conn_cache_pool_destroy(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern WT_THREAD_RET __wt_cache_pool_server(void *arg);
-extern int __wt_checkpoint_server_create(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_checkpoint_server_destroy(WT_SESSION_IMPL *session);
-extern int __wt_checkpoint_signal(WT_SESSION_IMPL *session, wt_off_t logsize);
-extern int __wt_conn_dhandle_find( WT_SESSION_IMPL *session, const char *uri, const char *checkpoint);
-extern int __wt_conn_btree_sync_and_close(WT_SESSION_IMPL *session, bool final, bool force);
-extern int __wt_conn_btree_open( WT_SESSION_IMPL *session, const char *cfg[], uint32_t flags);
-extern int __wt_conn_btree_apply(WT_SESSION_IMPL *session, const char *uri, int (*file_func)(WT_SESSION_IMPL *, const char *[]), int (*name_func)(WT_SESSION_IMPL *, const char *, bool *), const char *cfg[]);
-extern int __wt_conn_dhandle_close_all( WT_SESSION_IMPL *session, const char *uri, bool force);
-extern int __wt_conn_dhandle_discard_single( WT_SESSION_IMPL *session, bool final, bool force);
-extern int __wt_conn_dhandle_discard(WT_SESSION_IMPL *session);
-extern int __wt_connection_init(WT_CONNECTION_IMPL *conn);
-extern int __wt_connection_destroy(WT_CONNECTION_IMPL *conn);
-extern int __wt_logmgr_reconfig(WT_SESSION_IMPL *session, const char **cfg);
-extern int __wt_log_truncate_files( WT_SESSION_IMPL *session, WT_CURSOR *cursor, const char *cfg[]);
-extern int __wt_log_wrlsn(WT_SESSION_IMPL *session, int *yield);
-extern int __wt_logmgr_create(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_logmgr_open(WT_SESSION_IMPL *session);
-extern int __wt_logmgr_destroy(WT_SESSION_IMPL *session);
-extern int __wt_connection_open(WT_CONNECTION_IMPL *conn, const char *cfg[]);
-extern int __wt_connection_close(WT_CONNECTION_IMPL *conn);
-extern int __wt_connection_workers(WT_SESSION_IMPL *session, const char *cfg[]);
+extern int __wt_checkpoint_server_create(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_checkpoint_server_destroy(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_checkpoint_signal(WT_SESSION_IMPL *session, wt_off_t logsize) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_conn_dhandle_find( WT_SESSION_IMPL *session, const char *uri, const char *checkpoint) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_conn_btree_sync_and_close(WT_SESSION_IMPL *session, bool final, bool force) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_conn_btree_open( WT_SESSION_IMPL *session, const char *cfg[], uint32_t flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_conn_btree_apply(WT_SESSION_IMPL *session, const char *uri, int (*file_func)(WT_SESSION_IMPL *, const char *[]), int (*name_func)(WT_SESSION_IMPL *, const char *, bool *), const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_conn_dhandle_close_all( WT_SESSION_IMPL *session, const char *uri, bool force) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_conn_dhandle_discard_single( WT_SESSION_IMPL *session, bool final, bool force) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_conn_dhandle_discard(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_connection_init(WT_CONNECTION_IMPL *conn) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_connection_destroy(WT_CONNECTION_IMPL *conn) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logmgr_reconfig(WT_SESSION_IMPL *session, const char **cfg) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_truncate_files( WT_SESSION_IMPL *session, WT_CURSOR *cursor, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_wrlsn(WT_SESSION_IMPL *session, int *yield) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logmgr_create(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logmgr_open(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logmgr_destroy(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_connection_open(WT_CONNECTION_IMPL *conn, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_connection_close(WT_CONNECTION_IMPL *conn) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_connection_workers(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_conn_stat_init(WT_SESSION_IMPL *session);
-extern int __wt_statlog_log_one(WT_SESSION_IMPL *session);
-extern int __wt_statlog_create(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_statlog_destroy(WT_SESSION_IMPL *session, bool is_close);
-extern int __wt_sweep_config(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_sweep_create(WT_SESSION_IMPL *session);
-extern int __wt_sweep_destroy(WT_SESSION_IMPL *session);
-extern int __wt_curbackup_open(WT_SESSION_IMPL *session, const char *uri, const char *cfg[], WT_CURSOR **cursorp);
-extern int __wt_backup_file_remove(WT_SESSION_IMPL *session);
-extern int __wt_curbulk_init(WT_SESSION_IMPL *session, WT_CURSOR_BULK *cbulk, bool bitmap, bool skip_sort_check);
-extern int __wt_curconfig_open(WT_SESSION_IMPL *session, const char *uri, const char *cfg[], WT_CURSOR **cursorp);
-extern int __wt_curds_open( WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *owner, const char *cfg[], WT_DATA_SOURCE *dsrc, WT_CURSOR **cursorp);
-extern int __wt_curdump_create(WT_CURSOR *child, WT_CURSOR *owner, WT_CURSOR **cursorp);
-extern int __wt_curfile_update_check(WT_CURSOR *cursor);
-extern int __wt_curfile_open(WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *owner, const char *cfg[], WT_CURSOR **cursorp);
-extern int __wt_curindex_open(WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *owner, const char *cfg[], WT_CURSOR **cursorp);
-extern int __wt_curjoin_joined(WT_CURSOR *cursor);
-extern int __wt_curjoin_open(WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *owner, const char *cfg[], WT_CURSOR **cursorp);
-extern int __wt_curjoin_join(WT_SESSION_IMPL *session, WT_CURSOR_JOIN *cjoin, WT_INDEX *idx, WT_CURSOR *ref_cursor, uint8_t flags, uint8_t range, uint64_t count, uint32_t bloom_bit_count, uint32_t bloom_hash_count);
-extern int __wt_json_alloc_unpack(WT_SESSION_IMPL *session, const void *buffer, size_t size, const char *fmt, WT_CURSOR_JSON *json, bool iskey, va_list ap);
+extern int __wt_statlog_log_one(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_statlog_create(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_statlog_destroy(WT_SESSION_IMPL *session, bool is_close) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_sweep_config(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_sweep_create(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_sweep_destroy(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_curbackup_open(WT_SESSION_IMPL *session, const char *uri, const char *cfg[], WT_CURSOR **cursorp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_backup_file_remove(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_curbulk_init(WT_SESSION_IMPL *session, WT_CURSOR_BULK *cbulk, bool bitmap, bool skip_sort_check) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_curconfig_open(WT_SESSION_IMPL *session, const char *uri, const char *cfg[], WT_CURSOR **cursorp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_curds_open( WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *owner, const char *cfg[], WT_DATA_SOURCE *dsrc, WT_CURSOR **cursorp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_curdump_create(WT_CURSOR *child, WT_CURSOR *owner, WT_CURSOR **cursorp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_curfile_update_check(WT_CURSOR *cursor) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_curfile_open(WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *owner, const char *cfg[], WT_CURSOR **cursorp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_curindex_open(WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *owner, const char *cfg[], WT_CURSOR **cursorp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_curjoin_joined(WT_CURSOR *cursor) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_curjoin_open(WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *owner, const char *cfg[], WT_CURSOR **cursorp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_curjoin_join(WT_SESSION_IMPL *session, WT_CURSOR_JOIN *cjoin, WT_INDEX *idx, WT_CURSOR *ref_cursor, uint8_t flags, uint8_t range, uint64_t count, uint32_t bloom_bit_count, uint32_t bloom_hash_count) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_json_alloc_unpack(WT_SESSION_IMPL *session, const void *buffer, size_t size, const char *fmt, WT_CURSOR_JSON *json, bool iskey, va_list ap) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_json_close(WT_SESSION_IMPL *session, WT_CURSOR *cursor);
 extern size_t __wt_json_unpack_char(u_char ch, u_char *buf, size_t bufsz, bool force_unicode);
-extern int __wt_json_column_init(WT_CURSOR *cursor, const char *keyformat, const WT_CONFIG_ITEM *idxconf, const WT_CONFIG_ITEM *colconf);
-extern int __wt_json_token(WT_SESSION *wt_session, const char *src, int *toktype, const char **tokstart, size_t *toklen);
+extern int __wt_json_column_init(WT_CURSOR *cursor, const char *keyformat, const WT_CONFIG_ITEM *idxconf, const WT_CONFIG_ITEM *colconf) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_json_token(WT_SESSION *wt_session, const char *src, int *toktype, const char **tokstart, size_t *toklen) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern const char *__wt_json_tokname(int toktype);
-extern int __wt_json_to_item(WT_SESSION_IMPL *session, const char *jstr, const char *format, WT_CURSOR_JSON *json, bool iskey, WT_ITEM *item);
+extern int __wt_json_to_item(WT_SESSION_IMPL *session, const char *jstr, const char *format, WT_CURSOR_JSON *json, bool iskey, WT_ITEM *item) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern ssize_t __wt_json_strlen(const char *src, size_t srclen);
-extern int __wt_json_strncpy(WT_SESSION *wt_session, char **pdst, size_t dstlen, const char *src, size_t srclen);
-extern int __wt_curlog_open(WT_SESSION_IMPL *session, const char *uri, const char *cfg[], WT_CURSOR **cursorp);
-extern int __wt_schema_create_final( WT_SESSION_IMPL *session, char *cfg_arg[], char **value_ret);
-extern int __wt_curmetadata_open(WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *owner, const char *cfg[], WT_CURSOR **cursorp);
+extern int __wt_json_strncpy(WT_SESSION *wt_session, char **pdst, size_t dstlen, const char *src, size_t srclen) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_curlog_open(WT_SESSION_IMPL *session, const char *uri, const char *cfg[], WT_CURSOR **cursorp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_create_final( WT_SESSION_IMPL *session, char *cfg_arg[], char **value_ret) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_curmetadata_open(WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *owner, const char *cfg[], WT_CURSOR **cursorp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_curstat_dsrc_final(WT_CURSOR_STAT *cst);
-extern int __wt_curstat_init(WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *curjoin, const char *cfg[], WT_CURSOR_STAT *cst);
-extern int __wt_curstat_open(WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *other, const char *cfg[], WT_CURSOR **cursorp);
-extern int __wt_cursor_noop(WT_CURSOR *cursor);
-extern int __wt_cursor_notsup(WT_CURSOR *cursor);
-extern int __wt_cursor_get_value_notsup(WT_CURSOR *cursor, ...);
+extern int __wt_curstat_init(WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *curjoin, const char *cfg[], WT_CURSOR_STAT *cst) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_curstat_open(WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *other, const char *cfg[], WT_CURSOR **cursorp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cursor_noop(WT_CURSOR *cursor) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cursor_notsup(WT_CURSOR *cursor) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cursor_get_value_notsup(WT_CURSOR *cursor, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_cursor_set_key_notsup(WT_CURSOR *cursor, ...);
 extern void __wt_cursor_set_value_notsup(WT_CURSOR *cursor, ...);
-extern int __wt_cursor_compare_notsup(WT_CURSOR *a, WT_CURSOR *b, int *cmpp);
-extern int __wt_cursor_equals_notsup(WT_CURSOR *cursor, WT_CURSOR *other, int *equalp);
-extern int __wt_cursor_search_near_notsup(WT_CURSOR *cursor, int *exact);
-extern int __wt_cursor_reconfigure_notsup(WT_CURSOR *cursor, const char *config);
+extern int __wt_cursor_compare_notsup(WT_CURSOR *a, WT_CURSOR *b, int *cmpp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cursor_equals_notsup(WT_CURSOR *cursor, WT_CURSOR *other, int *equalp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cursor_search_near_notsup(WT_CURSOR *cursor, int *exact) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cursor_reconfigure_notsup(WT_CURSOR *cursor, const char *config) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_cursor_set_notsup(WT_CURSOR *cursor);
-extern int __wt_cursor_kv_not_set(WT_CURSOR *cursor, bool key);
-extern int __wt_cursor_get_key(WT_CURSOR *cursor, ...);
+extern int __wt_cursor_kv_not_set(WT_CURSOR *cursor, bool key) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cursor_get_key(WT_CURSOR *cursor, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_cursor_set_key(WT_CURSOR *cursor, ...);
-extern int __wt_cursor_get_raw_key(WT_CURSOR *cursor, WT_ITEM *key);
+extern int __wt_cursor_get_raw_key(WT_CURSOR *cursor, WT_ITEM *key) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_cursor_set_raw_key(WT_CURSOR *cursor, WT_ITEM *key);
-extern int __wt_cursor_get_raw_value(WT_CURSOR *cursor, WT_ITEM *value);
+extern int __wt_cursor_get_raw_value(WT_CURSOR *cursor, WT_ITEM *value) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_cursor_set_raw_value(WT_CURSOR *cursor, WT_ITEM *value);
-extern int __wt_cursor_get_keyv(WT_CURSOR *cursor, uint32_t flags, va_list ap);
+extern int __wt_cursor_get_keyv(WT_CURSOR *cursor, uint32_t flags, va_list ap) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_cursor_set_keyv(WT_CURSOR *cursor, uint32_t flags, va_list ap);
-extern int __wt_cursor_get_value(WT_CURSOR *cursor, ...);
-extern int __wt_cursor_get_valuev(WT_CURSOR *cursor, va_list ap);
+extern int __wt_cursor_get_value(WT_CURSOR *cursor, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cursor_get_valuev(WT_CURSOR *cursor, va_list ap) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_cursor_set_value(WT_CURSOR *cursor, ...);
 extern void __wt_cursor_set_valuev(WT_CURSOR *cursor, va_list ap);
-extern int __wt_cursor_close(WT_CURSOR *cursor);
-extern int __wt_cursor_equals(WT_CURSOR *cursor, WT_CURSOR *other, int *equalp);
-extern int __wt_cursor_reconfigure(WT_CURSOR *cursor, const char *config);
-extern int __wt_cursor_dup_position(WT_CURSOR *to_dup, WT_CURSOR *cursor);
-extern int __wt_cursor_init(WT_CURSOR *cursor, const char *uri, WT_CURSOR *owner, const char *cfg[], WT_CURSOR **cursorp);
-extern int __wt_apply_single_idx(WT_SESSION_IMPL *session, WT_INDEX *idx, WT_CURSOR *cur, WT_CURSOR_TABLE *ctable, int (*f)(WT_CURSOR *));
-extern int __wt_curtable_get_key(WT_CURSOR *cursor, ...);
-extern int __wt_curtable_get_value(WT_CURSOR *cursor, ...);
+extern int __wt_cursor_close(WT_CURSOR *cursor) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cursor_equals(WT_CURSOR *cursor, WT_CURSOR *other, int *equalp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cursor_reconfigure(WT_CURSOR *cursor, const char *config) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cursor_dup_position(WT_CURSOR *to_dup, WT_CURSOR *cursor) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cursor_init(WT_CURSOR *cursor, const char *uri, WT_CURSOR *owner, const char *cfg[], WT_CURSOR **cursorp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_apply_single_idx(WT_SESSION_IMPL *session, WT_INDEX *idx, WT_CURSOR *cur, WT_CURSOR_TABLE *ctable, int (*f)(WT_CURSOR *)) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_curtable_get_key(WT_CURSOR *cursor, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_curtable_get_value(WT_CURSOR *cursor, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_curtable_set_key(WT_CURSOR *cursor, ...);
 extern void __wt_curtable_set_value(WT_CURSOR *cursor, ...);
-extern int __wt_table_range_truncate(WT_CURSOR_TABLE *start, WT_CURSOR_TABLE *stop);
-extern int __wt_curtable_open(WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *owner, const char *cfg[], WT_CURSOR **cursorp);
-extern int __wt_evict_file(WT_SESSION_IMPL *session, WT_CACHE_OP syncop);
+extern int __wt_table_range_truncate(WT_CURSOR_TABLE *start, WT_CURSOR_TABLE *stop) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_curtable_open(WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *owner, const char *cfg[], WT_CURSOR **cursorp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_evict_file(WT_SESSION_IMPL *session, WT_CACHE_OP syncop) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_evict_list_clear_page(WT_SESSION_IMPL *session, WT_REF *ref);
-extern int __wt_evict_server_wake(WT_SESSION_IMPL *session);
-extern int __wt_evict_create(WT_SESSION_IMPL *session);
-extern int __wt_evict_destroy(WT_SESSION_IMPL *session);
-extern int __wt_evict_file_exclusive_on(WT_SESSION_IMPL *session);
+extern int __wt_evict_server_wake(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_evict_create(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_evict_destroy(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_evict_file_exclusive_on(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_evict_file_exclusive_off(WT_SESSION_IMPL *session);
-extern int __wt_cache_eviction_worker(WT_SESSION_IMPL *session, bool busy, u_int pct_full);
-extern int __wt_page_evict_soon(WT_SESSION_IMPL *session, WT_REF *ref);
+extern int __wt_cache_eviction_worker(WT_SESSION_IMPL *session, bool busy, u_int pct_full) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_page_evict_soon(WT_SESSION_IMPL *session, WT_REF *ref) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_evict_priority_set(WT_SESSION_IMPL *session, uint64_t v);
 extern void __wt_evict_priority_clear(WT_SESSION_IMPL *session);
-extern int __wt_cache_dump(WT_SESSION_IMPL *session, const char *ofile);
-extern int __wt_page_release_evict(WT_SESSION_IMPL *session, WT_REF *ref);
-extern int __wt_evict(WT_SESSION_IMPL *session, WT_REF *ref, bool closing);
-extern int __wt_log_ckpt(WT_SESSION_IMPL *session, WT_LSN *ckp_lsn);
-extern int __wt_log_flush_lsn(WT_SESSION_IMPL *session, WT_LSN *lsn, bool start);
-extern int __wt_log_background(WT_SESSION_IMPL *session, WT_LSN *lsn);
-extern int __wt_log_force_sync(WT_SESSION_IMPL *session, WT_LSN *min_lsn);
-extern int __wt_log_needs_recovery(WT_SESSION_IMPL *session, WT_LSN *ckp_lsn, bool *recp);
+extern int __wt_cache_dump(WT_SESSION_IMPL *session, const char *ofile) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_page_release_evict(WT_SESSION_IMPL *session, WT_REF *ref) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_evict(WT_SESSION_IMPL *session, WT_REF *ref, bool closing) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_ckpt(WT_SESSION_IMPL *session, WT_LSN *ckp_lsn) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_flush_lsn(WT_SESSION_IMPL *session, WT_LSN *lsn, bool start) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_background(WT_SESSION_IMPL *session, WT_LSN *lsn) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_force_sync(WT_SESSION_IMPL *session, WT_LSN *min_lsn) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_needs_recovery(WT_SESSION_IMPL *session, WT_LSN *ckp_lsn, bool *recp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_log_written_reset(WT_SESSION_IMPL *session);
-extern int __wt_log_get_all_files(WT_SESSION_IMPL *session, char ***filesp, u_int *countp, uint32_t *maxid, bool active_only);
-extern int __wt_log_extract_lognum( WT_SESSION_IMPL *session, const char *name, uint32_t *id);
-extern int __wt_log_acquire(WT_SESSION_IMPL *session, uint64_t recsize, WT_LOGSLOT *slot);
-extern int __wt_log_allocfile( WT_SESSION_IMPL *session, uint32_t lognum, const char *dest);
-extern int __wt_log_remove(WT_SESSION_IMPL *session, const char *file_prefix, uint32_t lognum);
-extern int __wt_log_open(WT_SESSION_IMPL *session);
-extern int __wt_log_close(WT_SESSION_IMPL *session);
-extern int __wt_log_release(WT_SESSION_IMPL *session, WT_LOGSLOT *slot, bool *freep);
-extern int __wt_log_scan(WT_SESSION_IMPL *session, WT_LSN *lsnp, uint32_t flags, int (*func)(WT_SESSION_IMPL *session, WT_ITEM *record, WT_LSN *lsnp, WT_LSN *next_lsnp, void *cookie, int firstrecord), void *cookie);
-extern int __wt_log_force_write(WT_SESSION_IMPL *session, bool retry, bool *did_work);
-extern int __wt_log_write(WT_SESSION_IMPL *session, WT_ITEM *record, WT_LSN *lsnp, uint32_t flags);
-extern int __wt_log_vprintf(WT_SESSION_IMPL *session, const char *fmt, va_list ap);
-extern int __wt_log_flush(WT_SESSION_IMPL *session, uint32_t flags);
-extern int __wt_logrec_alloc(WT_SESSION_IMPL *session, size_t size, WT_ITEM **logrecp);
+extern int __wt_log_get_all_files(WT_SESSION_IMPL *session, char ***filesp, u_int *countp, uint32_t *maxid, bool active_only) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_extract_lognum( WT_SESSION_IMPL *session, const char *name, uint32_t *id) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_acquire(WT_SESSION_IMPL *session, uint64_t recsize, WT_LOGSLOT *slot) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_allocfile( WT_SESSION_IMPL *session, uint32_t lognum, const char *dest) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_remove(WT_SESSION_IMPL *session, const char *file_prefix, uint32_t lognum) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_open(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_close(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_release(WT_SESSION_IMPL *session, WT_LOGSLOT *slot, bool *freep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_scan(WT_SESSION_IMPL *session, WT_LSN *lsnp, uint32_t flags, int (*func)(WT_SESSION_IMPL *session, WT_ITEM *record, WT_LSN *lsnp, WT_LSN *next_lsnp, void *cookie, int firstrecord), void *cookie) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_force_write(WT_SESSION_IMPL *session, bool retry, bool *did_work) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_write(WT_SESSION_IMPL *session, WT_ITEM *record, WT_LSN *lsnp, uint32_t flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_vprintf(WT_SESSION_IMPL *session, const char *fmt, va_list ap) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_flush(WT_SESSION_IMPL *session, uint32_t flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logrec_alloc(WT_SESSION_IMPL *session, size_t size, WT_ITEM **logrecp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_logrec_free(WT_SESSION_IMPL *session, WT_ITEM **logrecp);
-extern int __wt_logrec_read(WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t *rectypep);
-extern int __wt_logop_read(WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t *optypep, uint32_t *opsizep);
-extern int __wt_logop_col_put_pack( WT_SESSION_IMPL *session, WT_ITEM *logrec, uint32_t fileid, uint64_t recno, WT_ITEM *value);
-extern int __wt_logop_col_put_unpack( WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t *fileidp, uint64_t *recnop, WT_ITEM *valuep);
-extern int __wt_logop_col_put_print(WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t flags);
-extern int __wt_logop_col_remove_pack( WT_SESSION_IMPL *session, WT_ITEM *logrec, uint32_t fileid, uint64_t recno);
-extern int __wt_logop_col_remove_unpack( WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t *fileidp, uint64_t *recnop);
-extern int __wt_logop_col_remove_print(WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t flags);
-extern int __wt_logop_col_truncate_pack( WT_SESSION_IMPL *session, WT_ITEM *logrec, uint32_t fileid, uint64_t start, uint64_t stop);
-extern int __wt_logop_col_truncate_unpack( WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t *fileidp, uint64_t *startp, uint64_t *stopp);
-extern int __wt_logop_col_truncate_print(WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t flags);
-extern int __wt_logop_row_put_pack( WT_SESSION_IMPL *session, WT_ITEM *logrec, uint32_t fileid, WT_ITEM *key, WT_ITEM *value);
-extern int __wt_logop_row_put_unpack( WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t *fileidp, WT_ITEM *keyp, WT_ITEM *valuep);
-extern int __wt_logop_row_put_print(WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t flags);
-extern int __wt_logop_row_remove_pack( WT_SESSION_IMPL *session, WT_ITEM *logrec, uint32_t fileid, WT_ITEM *key);
-extern int __wt_logop_row_remove_unpack( WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t *fileidp, WT_ITEM *keyp);
-extern int __wt_logop_row_remove_print(WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t flags);
-extern int __wt_logop_row_truncate_pack( WT_SESSION_IMPL *session, WT_ITEM *logrec, uint32_t fileid, WT_ITEM *start, WT_ITEM *stop, uint32_t mode);
-extern int __wt_logop_row_truncate_unpack( WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t *fileidp, WT_ITEM *startp, WT_ITEM *stopp, uint32_t *modep);
-extern int __wt_logop_row_truncate_print(WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t flags);
-extern int __wt_txn_op_printlog(WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t flags);
+extern int __wt_logrec_read(WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t *rectypep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logop_read(WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t *optypep, uint32_t *opsizep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logop_col_put_pack( WT_SESSION_IMPL *session, WT_ITEM *logrec, uint32_t fileid, uint64_t recno, WT_ITEM *value) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logop_col_put_unpack( WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t *fileidp, uint64_t *recnop, WT_ITEM *valuep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logop_col_put_print(WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logop_col_remove_pack( WT_SESSION_IMPL *session, WT_ITEM *logrec, uint32_t fileid, uint64_t recno) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logop_col_remove_unpack( WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t *fileidp, uint64_t *recnop) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logop_col_remove_print(WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logop_col_truncate_pack( WT_SESSION_IMPL *session, WT_ITEM *logrec, uint32_t fileid, uint64_t start, uint64_t stop) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logop_col_truncate_unpack( WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t *fileidp, uint64_t *startp, uint64_t *stopp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logop_col_truncate_print(WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logop_row_put_pack( WT_SESSION_IMPL *session, WT_ITEM *logrec, uint32_t fileid, WT_ITEM *key, WT_ITEM *value) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logop_row_put_unpack( WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t *fileidp, WT_ITEM *keyp, WT_ITEM *valuep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logop_row_put_print(WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logop_row_remove_pack( WT_SESSION_IMPL *session, WT_ITEM *logrec, uint32_t fileid, WT_ITEM *key) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logop_row_remove_unpack( WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t *fileidp, WT_ITEM *keyp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logop_row_remove_print(WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logop_row_truncate_pack( WT_SESSION_IMPL *session, WT_ITEM *logrec, uint32_t fileid, WT_ITEM *start, WT_ITEM *stop, uint32_t mode) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logop_row_truncate_unpack( WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t *fileidp, WT_ITEM *startp, WT_ITEM *stopp, uint32_t *modep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_logop_row_truncate_print(WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_txn_op_printlog(WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, uint32_t flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_log_slot_activate(WT_SESSION_IMPL *session, WT_LOGSLOT *slot);
-extern int __wt_log_slot_switch( WT_SESSION_IMPL *session, WT_MYSLOT *myslot, bool retry, bool forced);
-extern int __wt_log_slot_new(WT_SESSION_IMPL *session);
-extern int __wt_log_slot_init(WT_SESSION_IMPL *session);
-extern int __wt_log_slot_destroy(WT_SESSION_IMPL *session);
+extern int __wt_log_slot_switch( WT_SESSION_IMPL *session, WT_MYSLOT *myslot, bool retry, bool forced) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_slot_new(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_slot_init(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_log_slot_destroy(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_log_slot_join(WT_SESSION_IMPL *session, uint64_t mysize, uint32_t flags, WT_MYSLOT *myslot);
 extern int64_t __wt_log_slot_release(WT_SESSION_IMPL *session, WT_MYSLOT *myslot, int64_t size);
 extern void __wt_log_slot_free(WT_SESSION_IMPL *session, WT_LOGSLOT *slot);
-extern int __wt_clsm_request_switch(WT_CURSOR_LSM *clsm);
-extern int __wt_clsm_await_switch(WT_CURSOR_LSM *clsm);
-extern int __wt_clsm_init_merge( WT_CURSOR *cursor, u_int start_chunk, uint32_t start_id, u_int nchunks);
-extern int __wt_clsm_close(WT_CURSOR *cursor);
-extern int __wt_clsm_open(WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *owner, const char *cfg[], WT_CURSOR **cursorp);
-extern int __wt_clsm_open_bulk(WT_CURSOR_LSM *clsm, const char *cfg[]);
-extern int __wt_lsm_manager_config(WT_SESSION_IMPL *session, const char **cfg);
-extern int __wt_lsm_manager_reconfig(WT_SESSION_IMPL *session, const char **cfg);
-extern int __wt_lsm_manager_start(WT_SESSION_IMPL *session);
+extern int __wt_clsm_request_switch(WT_CURSOR_LSM *clsm) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_clsm_await_switch(WT_CURSOR_LSM *clsm) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_clsm_init_merge( WT_CURSOR *cursor, u_int start_chunk, uint32_t start_id, u_int nchunks) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_clsm_close(WT_CURSOR *cursor) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_clsm_open(WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *owner, const char *cfg[], WT_CURSOR **cursorp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_clsm_open_bulk(WT_CURSOR_LSM *clsm, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_manager_config(WT_SESSION_IMPL *session, const char **cfg) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_manager_reconfig(WT_SESSION_IMPL *session, const char **cfg) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_manager_start(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_lsm_manager_free_work_unit( WT_SESSION_IMPL *session, WT_LSM_WORK_UNIT *entry);
-extern int __wt_lsm_manager_destroy(WT_SESSION_IMPL *session);
-extern int __wt_lsm_manager_clear_tree( WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree);
-extern int __wt_lsm_manager_pop_entry( WT_SESSION_IMPL *session, uint32_t type, WT_LSM_WORK_UNIT **entryp);
-extern int __wt_lsm_manager_push_entry(WT_SESSION_IMPL *session, uint32_t type, uint32_t flags, WT_LSM_TREE *lsm_tree);
-extern int __wt_lsm_merge_update_tree(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree, u_int start_chunk, u_int nchunks, WT_LSM_CHUNK *chunk);
-extern int __wt_lsm_merge(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree, u_int id);
-extern int __wt_lsm_meta_read(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree);
-extern int __wt_lsm_meta_write(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree);
-extern int __wt_curstat_lsm_init( WT_SESSION_IMPL *session, const char *uri, WT_CURSOR_STAT *cst);
-extern int __wt_lsm_tree_close_all(WT_SESSION_IMPL *session);
-extern int __wt_lsm_tree_bloom_name(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree, uint32_t id, const char **retp);
-extern int __wt_lsm_tree_chunk_name(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree, uint32_t id, const char **retp);
-extern int __wt_lsm_tree_set_chunk_size( WT_SESSION_IMPL *session, WT_LSM_CHUNK *chunk);
-extern int __wt_lsm_tree_setup_chunk( WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree, WT_LSM_CHUNK *chunk);
-extern int __wt_lsm_tree_setup_bloom( WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree, WT_LSM_CHUNK *chunk);
-extern int __wt_lsm_tree_create(WT_SESSION_IMPL *session, const char *uri, bool exclusive, const char *config);
-extern int __wt_lsm_tree_get(WT_SESSION_IMPL *session, const char *uri, bool exclusive, WT_LSM_TREE **treep);
+extern int __wt_lsm_manager_destroy(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_manager_clear_tree( WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_manager_pop_entry( WT_SESSION_IMPL *session, uint32_t type, WT_LSM_WORK_UNIT **entryp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_manager_push_entry(WT_SESSION_IMPL *session, uint32_t type, uint32_t flags, WT_LSM_TREE *lsm_tree) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_merge_update_tree(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree, u_int start_chunk, u_int nchunks, WT_LSM_CHUNK *chunk) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_merge(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree, u_int id) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_meta_read(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_meta_write(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_curstat_lsm_init( WT_SESSION_IMPL *session, const char *uri, WT_CURSOR_STAT *cst) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_tree_close_all(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_tree_bloom_name(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree, uint32_t id, const char **retp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_tree_chunk_name(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree, uint32_t id, const char **retp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_tree_set_chunk_size( WT_SESSION_IMPL *session, WT_LSM_CHUNK *chunk) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_tree_setup_chunk( WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree, WT_LSM_CHUNK *chunk) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_tree_setup_bloom( WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree, WT_LSM_CHUNK *chunk) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_tree_create(WT_SESSION_IMPL *session, const char *uri, bool exclusive, const char *config) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_tree_get(WT_SESSION_IMPL *session, const char *uri, bool exclusive, WT_LSM_TREE **treep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_lsm_tree_release(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree);
 extern void __wt_lsm_tree_throttle( WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree, bool decrease_only);
-extern int __wt_lsm_tree_switch(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree);
-extern int __wt_lsm_tree_retire_chunks(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree, u_int start_chunk, u_int nchunks);
-extern int __wt_lsm_tree_drop( WT_SESSION_IMPL *session, const char *name, const char *cfg[]);
-extern int __wt_lsm_tree_rename(WT_SESSION_IMPL *session, const char *olduri, const char *newuri, const char *cfg[]);
-extern int __wt_lsm_tree_truncate( WT_SESSION_IMPL *session, const char *name, const char *cfg[]);
-extern int __wt_lsm_tree_readlock(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree);
-extern int __wt_lsm_tree_readunlock(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree);
-extern int __wt_lsm_tree_writelock(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree);
-extern int __wt_lsm_tree_writeunlock(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree);
-extern int __wt_lsm_compact(WT_SESSION_IMPL *session, const char *name, bool *skipp);
-extern int __wt_lsm_tree_worker(WT_SESSION_IMPL *session, const char *uri, int (*file_func)(WT_SESSION_IMPL *, const char *[]), int (*name_func)(WT_SESSION_IMPL *, const char *, bool *), const char *cfg[], uint32_t open_flags);
-extern int __wt_lsm_get_chunk_to_flush(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree, bool force, WT_LSM_CHUNK **chunkp);
-extern int __wt_lsm_work_switch( WT_SESSION_IMPL *session, WT_LSM_WORK_UNIT **entryp, bool *ran);
-extern int __wt_lsm_work_bloom(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree);
-extern int __wt_lsm_checkpoint_chunk(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree, WT_LSM_CHUNK *chunk);
-extern int __wt_lsm_free_chunks(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree);
-extern int __wt_lsm_worker_start(WT_SESSION_IMPL *session, WT_LSM_WORKER_ARGS *args);
-extern int __wt_meta_apply_all(WT_SESSION_IMPL *session, int (*file_func)(WT_SESSION_IMPL *, const char *[]), int (*name_func)(WT_SESSION_IMPL *, const char *, bool *), const char *cfg[]);
-extern int __wt_meta_checkpoint(WT_SESSION_IMPL *session, const char *fname, const char *checkpoint, WT_CKPT *ckpt);
-extern int __wt_meta_checkpoint_last_name( WT_SESSION_IMPL *session, const char *fname, const char **namep);
-extern int __wt_meta_checkpoint_clear(WT_SESSION_IMPL *session, const char *fname);
-extern int __wt_meta_ckptlist_get( WT_SESSION_IMPL *session, const char *fname, WT_CKPT **ckptbasep);
-extern int __wt_meta_ckptlist_set(WT_SESSION_IMPL *session, const char *fname, WT_CKPT *ckptbase, WT_LSN *ckptlsn);
+extern int __wt_lsm_tree_switch(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_tree_retire_chunks(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree, u_int start_chunk, u_int nchunks) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_tree_drop( WT_SESSION_IMPL *session, const char *name, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_tree_rename(WT_SESSION_IMPL *session, const char *olduri, const char *newuri, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_tree_truncate( WT_SESSION_IMPL *session, const char *name, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_tree_readlock(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_tree_readunlock(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_tree_writelock(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_tree_writeunlock(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_compact(WT_SESSION_IMPL *session, const char *name, bool *skipp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_tree_worker(WT_SESSION_IMPL *session, const char *uri, int (*file_func)(WT_SESSION_IMPL *, const char *[]), int (*name_func)(WT_SESSION_IMPL *, const char *, bool *), const char *cfg[], uint32_t open_flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_get_chunk_to_flush(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree, bool force, WT_LSM_CHUNK **chunkp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_work_switch( WT_SESSION_IMPL *session, WT_LSM_WORK_UNIT **entryp, bool *ran) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_work_bloom(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_checkpoint_chunk(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree, WT_LSM_CHUNK *chunk) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_free_chunks(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_worker_start(WT_SESSION_IMPL *session, WT_LSM_WORKER_ARGS *args) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_meta_apply_all(WT_SESSION_IMPL *session, int (*file_func)(WT_SESSION_IMPL *, const char *[]), int (*name_func)(WT_SESSION_IMPL *, const char *, bool *), const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_meta_checkpoint(WT_SESSION_IMPL *session, const char *fname, const char *checkpoint, WT_CKPT *ckpt) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_meta_checkpoint_last_name( WT_SESSION_IMPL *session, const char *fname, const char **namep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_meta_checkpoint_clear(WT_SESSION_IMPL *session, const char *fname) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_meta_ckptlist_get( WT_SESSION_IMPL *session, const char *fname, WT_CKPT **ckptbasep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_meta_ckptlist_set(WT_SESSION_IMPL *session, const char *fname, WT_CKPT *ckptbase, WT_LSN *ckptlsn) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_meta_ckptlist_free(WT_SESSION_IMPL *session, WT_CKPT *ckptbase);
 extern void __wt_meta_checkpoint_free(WT_SESSION_IMPL *session, WT_CKPT *ckpt);
-extern int __wt_ext_metadata_insert(WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, const char *key, const char *value);
-extern int __wt_ext_metadata_remove( WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, const char *key);
-extern int __wt_ext_metadata_search(WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, const char *key, char **valuep);
-extern int __wt_ext_metadata_update(WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, const char *key, const char *value);
-extern int __wt_metadata_get_ckptlist( WT_SESSION *session, const char *name, WT_CKPT **ckptbasep);
+extern int __wt_ext_metadata_insert(WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, const char *key, const char *value) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ext_metadata_remove( WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, const char *key) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ext_metadata_search(WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, const char *key, char **valuep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ext_metadata_update(WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, const char *key, const char *value) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_metadata_get_ckptlist( WT_SESSION *session, const char *name, WT_CKPT **ckptbasep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_metadata_free_ckptlist(WT_SESSION *session, WT_CKPT *ckptbase);
-extern int __wt_metadata_cursor_open( WT_SESSION_IMPL *session, const char *config, WT_CURSOR **cursorp);
-extern int __wt_metadata_cursor(WT_SESSION_IMPL *session, WT_CURSOR **cursorp);
-extern int __wt_metadata_cursor_release(WT_SESSION_IMPL *session, WT_CURSOR **cursorp);
-extern int __wt_metadata_insert( WT_SESSION_IMPL *session, const char *key, const char *value);
-extern int __wt_metadata_update( WT_SESSION_IMPL *session, const char *key, const char *value);
-extern int __wt_metadata_remove(WT_SESSION_IMPL *session, const char *key);
-extern int __wt_metadata_search(WT_SESSION_IMPL *session, const char *key, char **valuep);
+extern int __wt_metadata_cursor_open( WT_SESSION_IMPL *session, const char *config, WT_CURSOR **cursorp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_metadata_cursor(WT_SESSION_IMPL *session, WT_CURSOR **cursorp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_metadata_cursor_release(WT_SESSION_IMPL *session, WT_CURSOR **cursorp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_metadata_insert( WT_SESSION_IMPL *session, const char *key, const char *value) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_metadata_update( WT_SESSION_IMPL *session, const char *key, const char *value) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_metadata_remove(WT_SESSION_IMPL *session, const char *key) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_metadata_search(WT_SESSION_IMPL *session, const char *key, char **valuep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_meta_track_discard(WT_SESSION_IMPL *session);
-extern int __wt_meta_track_on(WT_SESSION_IMPL *session);
-extern int __wt_meta_track_off(WT_SESSION_IMPL *session, bool need_sync, bool unroll);
-extern int __wt_meta_track_sub_on(WT_SESSION_IMPL *session);
-extern int __wt_meta_track_sub_off(WT_SESSION_IMPL *session);
-extern int __wt_meta_track_checkpoint(WT_SESSION_IMPL *session);
-extern int __wt_meta_track_insert(WT_SESSION_IMPL *session, const char *key);
-extern int __wt_meta_track_update(WT_SESSION_IMPL *session, const char *key);
-extern int __wt_meta_track_fileop( WT_SESSION_IMPL *session, const char *olduri, const char *newuri);
-extern int __wt_meta_track_drop( WT_SESSION_IMPL *session, const char *filename);
-extern int __wt_meta_track_handle_lock(WT_SESSION_IMPL *session, bool created);
-extern int __wt_meta_track_init(WT_SESSION_IMPL *session);
-extern int __wt_meta_track_destroy(WT_SESSION_IMPL *session);
-extern int __wt_turtle_init(WT_SESSION_IMPL *session);
-extern int __wt_turtle_read(WT_SESSION_IMPL *session, const char *key, char **valuep);
-extern int __wt_turtle_update(WT_SESSION_IMPL *session, const char *key, const char *value);
-extern int __wt_filename(WT_SESSION_IMPL *session, const char *name, char **path);
-extern int __wt_nfilename( WT_SESSION_IMPL *session, const char *name, size_t namelen, char **path);
-extern int __wt_remove_if_exists(WT_SESSION_IMPL *session, const char *name, bool durable);
-extern int __wt_copy_and_sync(WT_SESSION *wt_session, const char *from, const char *to);
+extern int __wt_meta_track_on(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_meta_track_off(WT_SESSION_IMPL *session, bool need_sync, bool unroll) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_meta_track_sub_on(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_meta_track_sub_off(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_meta_track_checkpoint(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_meta_track_insert(WT_SESSION_IMPL *session, const char *key) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_meta_track_update(WT_SESSION_IMPL *session, const char *key) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_meta_track_fileop( WT_SESSION_IMPL *session, const char *olduri, const char *newuri) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_meta_track_drop( WT_SESSION_IMPL *session, const char *filename) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_meta_track_handle_lock(WT_SESSION_IMPL *session, bool created) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_meta_track_init(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_meta_track_destroy(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_turtle_init(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_turtle_read(WT_SESSION_IMPL *session, const char *key, char **valuep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_turtle_update(WT_SESSION_IMPL *session, const char *key, const char *value) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_filename(WT_SESSION_IMPL *session, const char *name, char **path) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_nfilename( WT_SESSION_IMPL *session, const char *name, size_t namelen, char **path) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_remove_if_exists(WT_SESSION_IMPL *session, const char *name, bool durable) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_copy_and_sync(WT_SESSION *wt_session, const char *from, const char *to) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_abort(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((noreturn));
-extern int __wt_calloc(WT_SESSION_IMPL *session, size_t number, size_t size, void *retp);
-extern int __wt_malloc(WT_SESSION_IMPL *session, size_t bytes_to_allocate, void *retp);
-extern int __wt_realloc(WT_SESSION_IMPL *session, size_t *bytes_allocated_ret, size_t bytes_to_allocate, void *retp);
-extern int __wt_realloc_noclear(WT_SESSION_IMPL *session, size_t *bytes_allocated_ret, size_t bytes_to_allocate, void *retp);
-extern int __wt_realloc_aligned(WT_SESSION_IMPL *session, size_t *bytes_allocated_ret, size_t bytes_to_allocate, void *retp);
-extern int __wt_strndup(WT_SESSION_IMPL *session, const void *str, size_t len, void *retp);
+extern int __wt_calloc(WT_SESSION_IMPL *session, size_t number, size_t size, void *retp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_malloc(WT_SESSION_IMPL *session, size_t bytes_to_allocate, void *retp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_realloc(WT_SESSION_IMPL *session, size_t *bytes_allocated_ret, size_t bytes_to_allocate, void *retp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_realloc_noclear(WT_SESSION_IMPL *session, size_t *bytes_allocated_ret, size_t bytes_to_allocate, void *retp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_realloc_aligned(WT_SESSION_IMPL *session, size_t *bytes_allocated_ret, size_t bytes_to_allocate, void *retp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_strndup(WT_SESSION_IMPL *session, const void *str, size_t len, void *retp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_free_int(WT_SESSION_IMPL *session, const void *p_arg);
-extern int __wt_errno(void);
+extern int __wt_errno(void) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern const char *__wt_strerror(WT_SESSION_IMPL *session, int error, char *errbuf, size_t errlen);
-extern int __wt_ext_map_windows_error( WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, uint32_t windows_error);
+extern int __wt_ext_map_windows_error( WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, uint32_t windows_error) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern bool __wt_handle_is_open(WT_SESSION_IMPL *session, const char *name);
-extern int __wt_open(WT_SESSION_IMPL *session, const char *name, WT_FS_OPEN_FILE_TYPE file_type, u_int flags, WT_FH **fhp);
-extern int __wt_close(WT_SESSION_IMPL *session, WT_FH **fhp);
-extern int __wt_close_connection_close(WT_SESSION_IMPL *session);
-extern int __wt_os_inmemory(WT_SESSION_IMPL *session);
-extern int __wt_fopen(WT_SESSION_IMPL *session, const char *name, uint32_t open_flags, uint32_t flags, WT_FSTREAM **fstrp);
-extern int __wt_os_stdio(WT_SESSION_IMPL *session);
-extern int __wt_getopt( const char *progname, int nargc, char *const *nargv, const char *ostr);
+extern int __wt_open(WT_SESSION_IMPL *session, const char *name, WT_FS_OPEN_FILE_TYPE file_type, u_int flags, WT_FH **fhp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_close(WT_SESSION_IMPL *session, WT_FH **fhp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_close_connection_close(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_os_inmemory(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_fopen(WT_SESSION_IMPL *session, const char *name, uint32_t open_flags, uint32_t flags, WT_FSTREAM **fstrp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_os_stdio(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_getopt( const char *progname, int nargc, char *const *nargv, const char *ostr) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern uint64_t __wt_strtouq(const char *nptr, char **endptr, int base);
-extern int __wt_ext_struct_pack(WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, void *buffer, size_t size, const char *fmt, ...);
-extern int __wt_ext_struct_size(WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, size_t *sizep, const char *fmt, ...);
-extern int __wt_ext_struct_unpack(WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, const void *buffer, size_t size, const char *fmt, ...);
-extern int __wt_struct_check(WT_SESSION_IMPL *session, const char *fmt, size_t len, bool *fixedp, uint32_t *fixed_lenp);
-extern int __wt_struct_confchk(WT_SESSION_IMPL *session, WT_CONFIG_ITEM *v);
-extern int __wt_struct_size(WT_SESSION_IMPL *session, size_t *sizep, const char *fmt, ...);
-extern int __wt_struct_pack(WT_SESSION_IMPL *session, void *buffer, size_t size, const char *fmt, ...);
-extern int __wt_struct_unpack(WT_SESSION_IMPL *session, const void *buffer, size_t size, const char *fmt, ...);
-extern int __wt_struct_repack(WT_SESSION_IMPL *session, const char *infmt, const char *outfmt, const WT_ITEM *inbuf, WT_ITEM *outbuf);
-extern int __wt_ext_pack_start(WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, const char *format, void *buffer, size_t size, WT_PACK_STREAM **psp);
-extern int __wt_ext_unpack_start(WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, const char *format, const void *buffer, size_t size, WT_PACK_STREAM **psp);
-extern int __wt_ext_pack_close(WT_EXTENSION_API *wt_api, WT_PACK_STREAM *ps, size_t *usedp);
-extern int __wt_ext_pack_item(WT_EXTENSION_API *wt_api, WT_PACK_STREAM *ps, WT_ITEM *item);
-extern int __wt_ext_pack_int(WT_EXTENSION_API *wt_api, WT_PACK_STREAM *ps, int64_t i);
-extern int __wt_ext_pack_str(WT_EXTENSION_API *wt_api, WT_PACK_STREAM *ps, const char *s);
-extern int __wt_ext_pack_uint(WT_EXTENSION_API *wt_api, WT_PACK_STREAM *ps, uint64_t u);
-extern int __wt_ext_unpack_item(WT_EXTENSION_API *wt_api, WT_PACK_STREAM *ps, WT_ITEM *item);
-extern int __wt_ext_unpack_int(WT_EXTENSION_API *wt_api, WT_PACK_STREAM *ps, int64_t *ip);
-extern int __wt_ext_unpack_str(WT_EXTENSION_API *wt_api, WT_PACK_STREAM *ps, const char **sp);
-extern int __wt_ext_unpack_uint(WT_EXTENSION_API *wt_api, WT_PACK_STREAM *ps, uint64_t *up);
-extern int __wt_ovfl_discard_add(WT_SESSION_IMPL *session, WT_PAGE *page, WT_CELL *cell);
+extern int __wt_ext_struct_pack(WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, void *buffer, size_t size, const char *fmt, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ext_struct_size(WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, size_t *sizep, const char *fmt, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ext_struct_unpack(WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, const void *buffer, size_t size, const char *fmt, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_struct_check(WT_SESSION_IMPL *session, const char *fmt, size_t len, bool *fixedp, uint32_t *fixed_lenp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_struct_confchk(WT_SESSION_IMPL *session, WT_CONFIG_ITEM *v) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_struct_size(WT_SESSION_IMPL *session, size_t *sizep, const char *fmt, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_struct_pack(WT_SESSION_IMPL *session, void *buffer, size_t size, const char *fmt, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_struct_unpack(WT_SESSION_IMPL *session, const void *buffer, size_t size, const char *fmt, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_struct_repack(WT_SESSION_IMPL *session, const char *infmt, const char *outfmt, const WT_ITEM *inbuf, WT_ITEM *outbuf) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ext_pack_start(WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, const char *format, void *buffer, size_t size, WT_PACK_STREAM **psp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ext_unpack_start(WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, const char *format, const void *buffer, size_t size, WT_PACK_STREAM **psp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ext_pack_close(WT_EXTENSION_API *wt_api, WT_PACK_STREAM *ps, size_t *usedp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ext_pack_item(WT_EXTENSION_API *wt_api, WT_PACK_STREAM *ps, WT_ITEM *item) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ext_pack_int(WT_EXTENSION_API *wt_api, WT_PACK_STREAM *ps, int64_t i) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ext_pack_str(WT_EXTENSION_API *wt_api, WT_PACK_STREAM *ps, const char *s) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ext_pack_uint(WT_EXTENSION_API *wt_api, WT_PACK_STREAM *ps, uint64_t u) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ext_unpack_item(WT_EXTENSION_API *wt_api, WT_PACK_STREAM *ps, WT_ITEM *item) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ext_unpack_int(WT_EXTENSION_API *wt_api, WT_PACK_STREAM *ps, int64_t *ip) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ext_unpack_str(WT_EXTENSION_API *wt_api, WT_PACK_STREAM *ps, const char **sp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ext_unpack_uint(WT_EXTENSION_API *wt_api, WT_PACK_STREAM *ps, uint64_t *up) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ovfl_discard_add(WT_SESSION_IMPL *session, WT_PAGE *page, WT_CELL *cell) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_ovfl_discard_free(WT_SESSION_IMPL *session, WT_PAGE *page);
-extern int __wt_ovfl_reuse_search(WT_SESSION_IMPL *session, WT_PAGE *page, uint8_t **addrp, size_t *addr_sizep, const void *value, size_t value_size);
-extern int __wt_ovfl_reuse_add(WT_SESSION_IMPL *session, WT_PAGE *page, const uint8_t *addr, size_t addr_size, const void *value, size_t value_size);
+extern int __wt_ovfl_reuse_search(WT_SESSION_IMPL *session, WT_PAGE *page, uint8_t **addrp, size_t *addr_sizep, const void *value, size_t value_size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ovfl_reuse_add(WT_SESSION_IMPL *session, WT_PAGE *page, const uint8_t *addr, size_t addr_size, const void *value, size_t value_size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_ovfl_reuse_free(WT_SESSION_IMPL *session, WT_PAGE *page);
-extern int __wt_ovfl_txnc_search( WT_PAGE *page, const uint8_t *addr, size_t addr_size, WT_ITEM *store);
-extern int __wt_ovfl_txnc_add(WT_SESSION_IMPL *session, WT_PAGE *page, const uint8_t *addr, size_t addr_size, const void *value, size_t value_size);
+extern int __wt_ovfl_txnc_search( WT_PAGE *page, const uint8_t *addr, size_t addr_size, WT_ITEM *store) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ovfl_txnc_add(WT_SESSION_IMPL *session, WT_PAGE *page, const uint8_t *addr, size_t addr_size, const void *value, size_t value_size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_ovfl_txnc_free(WT_SESSION_IMPL *session, WT_PAGE *page);
-extern int __wt_ovfl_track_wrapup(WT_SESSION_IMPL *session, WT_PAGE *page);
-extern int __wt_ovfl_track_wrapup_err(WT_SESSION_IMPL *session, WT_PAGE *page);
-extern int __wt_reconcile(WT_SESSION_IMPL *session, WT_REF *ref, WT_SALVAGE_COOKIE *salvage, uint32_t flags);
+extern int __wt_ovfl_track_wrapup(WT_SESSION_IMPL *session, WT_PAGE *page) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ovfl_track_wrapup_err(WT_SESSION_IMPL *session, WT_PAGE *page) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_reconcile(WT_SESSION_IMPL *session, WT_REF *ref, WT_SALVAGE_COOKIE *salvage, uint32_t flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern uint32_t __wt_split_page_size(WT_BTREE *btree, uint32_t maxpagesize);
-extern int __wt_bulk_init(WT_SESSION_IMPL *session, WT_CURSOR_BULK *cbulk);
-extern int __wt_bulk_wrapup(WT_SESSION_IMPL *session, WT_CURSOR_BULK *cbulk);
-extern int __wt_bulk_insert_row(WT_SESSION_IMPL *session, WT_CURSOR_BULK *cbulk);
-extern int __wt_bulk_insert_fix( WT_SESSION_IMPL *session, WT_CURSOR_BULK *cbulk, bool deleted);
-extern int __wt_bulk_insert_fix_bitmap(WT_SESSION_IMPL *session, WT_CURSOR_BULK *cbulk);
-extern int __wt_bulk_insert_var( WT_SESSION_IMPL *session, WT_CURSOR_BULK *cbulk, bool deleted);
-extern int __wt_direct_io_size_check(WT_SESSION_IMPL *session, const char **cfg, const char *config_name, uint32_t *allocsizep);
-extern int __wt_schema_colgroup_source(WT_SESSION_IMPL *session, WT_TABLE *table, const char *cgname, const char *config, WT_ITEM *buf);
-extern int __wt_schema_index_source(WT_SESSION_IMPL *session, WT_TABLE *table, const char *idxname, const char *config, WT_ITEM *buf);
-extern int __wt_schema_create( WT_SESSION_IMPL *session, const char *uri, const char *config);
-extern int __wt_schema_drop(WT_SESSION_IMPL *session, const char *uri, const char *cfg[]);
-extern int __wt_schema_get_table(WT_SESSION_IMPL *session, const char *name, size_t namelen, bool ok_incomplete, WT_TABLE **tablep);
+extern int __wt_bulk_init(WT_SESSION_IMPL *session, WT_CURSOR_BULK *cbulk) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_bulk_wrapup(WT_SESSION_IMPL *session, WT_CURSOR_BULK *cbulk) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_bulk_insert_row(WT_SESSION_IMPL *session, WT_CURSOR_BULK *cbulk) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_bulk_insert_fix( WT_SESSION_IMPL *session, WT_CURSOR_BULK *cbulk, bool deleted) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_bulk_insert_fix_bitmap(WT_SESSION_IMPL *session, WT_CURSOR_BULK *cbulk) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_bulk_insert_var( WT_SESSION_IMPL *session, WT_CURSOR_BULK *cbulk, bool deleted) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_direct_io_size_check(WT_SESSION_IMPL *session, const char **cfg, const char *config_name, uint32_t *allocsizep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_colgroup_source(WT_SESSION_IMPL *session, WT_TABLE *table, const char *cgname, const char *config, WT_ITEM *buf) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_index_source(WT_SESSION_IMPL *session, WT_TABLE *table, const char *idxname, const char *config, WT_ITEM *buf) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_create( WT_SESSION_IMPL *session, const char *uri, const char *config) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_drop(WT_SESSION_IMPL *session, const char *uri, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_get_table(WT_SESSION_IMPL *session, const char *name, size_t namelen, bool ok_incomplete, WT_TABLE **tablep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_schema_release_table(WT_SESSION_IMPL *session, WT_TABLE *table);
 extern void __wt_schema_destroy_colgroup(WT_SESSION_IMPL *session, WT_COLGROUP **colgroupp);
-extern int __wt_schema_destroy_index(WT_SESSION_IMPL *session, WT_INDEX **idxp);
-extern int __wt_schema_destroy_table(WT_SESSION_IMPL *session, WT_TABLE **tablep);
-extern int __wt_schema_remove_table(WT_SESSION_IMPL *session, WT_TABLE *table);
-extern int __wt_schema_close_tables(WT_SESSION_IMPL *session);
-extern int __wt_schema_colgroup_name(WT_SESSION_IMPL *session, WT_TABLE *table, const char *cgname, size_t len, WT_ITEM *buf);
-extern int __wt_schema_open_colgroups(WT_SESSION_IMPL *session, WT_TABLE *table);
-extern int __wt_schema_open_index(WT_SESSION_IMPL *session, WT_TABLE *table, const char *idxname, size_t len, WT_INDEX **indexp);
-extern int __wt_schema_open_indices(WT_SESSION_IMPL *session, WT_TABLE *table);
-extern int __wt_schema_get_colgroup(WT_SESSION_IMPL *session, const char *uri, bool quiet, WT_TABLE **tablep, WT_COLGROUP **colgroupp);
-extern int __wt_schema_get_index(WT_SESSION_IMPL *session, const char *uri, bool quiet, WT_TABLE **tablep, WT_INDEX **indexp);
-extern int __wt_schema_open_table(WT_SESSION_IMPL *session, const char *name, size_t namelen, bool ok_incomplete, WT_TABLE **tablep);
-extern int __wt_schema_colcheck(WT_SESSION_IMPL *session, const char *key_format, const char *value_format, WT_CONFIG_ITEM *colconf, u_int *kcolsp, u_int *vcolsp);
-extern int __wt_table_check(WT_SESSION_IMPL *session, WT_TABLE *table);
-extern int __wt_struct_plan(WT_SESSION_IMPL *session, WT_TABLE *table, const char *columns, size_t len, bool value_only, WT_ITEM *plan);
-extern int __wt_struct_reformat(WT_SESSION_IMPL *session, WT_TABLE *table, const char *columns, size_t len, const char *extra_cols, bool value_only, WT_ITEM *format);
-extern int __wt_struct_truncate(WT_SESSION_IMPL *session, const char *input_fmt, u_int ncols, WT_ITEM *format);
-extern int __wt_schema_project_in(WT_SESSION_IMPL *session, WT_CURSOR **cp, const char *proj_arg, va_list ap);
-extern int __wt_schema_project_out(WT_SESSION_IMPL *session, WT_CURSOR **cp, const char *proj_arg, va_list ap);
-extern int __wt_schema_project_slice(WT_SESSION_IMPL *session, WT_CURSOR **cp, const char *proj_arg, bool key_only, const char *vformat, WT_ITEM *value);
-extern int __wt_schema_project_merge(WT_SESSION_IMPL *session, WT_CURSOR **cp, const char *proj_arg, const char *vformat, WT_ITEM *value);
-extern int __wt_schema_rename(WT_SESSION_IMPL *session, const char *uri, const char *newuri, const char *cfg[]);
-extern int __wt_curstat_colgroup_init(WT_SESSION_IMPL *session, const char *uri, const char *cfg[], WT_CURSOR_STAT *cst);
-extern int __wt_curstat_index_init(WT_SESSION_IMPL *session, const char *uri, const char *cfg[], WT_CURSOR_STAT *cst);
-extern int __wt_curstat_table_init(WT_SESSION_IMPL *session, const char *uri, const char *cfg[], WT_CURSOR_STAT *cst);
-extern int __wt_schema_truncate( WT_SESSION_IMPL *session, const char *uri, const char *cfg[]);
-extern int __wt_range_truncate(WT_CURSOR *start, WT_CURSOR *stop);
-extern int __wt_schema_range_truncate( WT_SESSION_IMPL *session, WT_CURSOR *start, WT_CURSOR *stop);
+extern int __wt_schema_destroy_index(WT_SESSION_IMPL *session, WT_INDEX **idxp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_destroy_table(WT_SESSION_IMPL *session, WT_TABLE **tablep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_remove_table(WT_SESSION_IMPL *session, WT_TABLE *table) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_close_tables(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_colgroup_name(WT_SESSION_IMPL *session, WT_TABLE *table, const char *cgname, size_t len, WT_ITEM *buf) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_open_colgroups(WT_SESSION_IMPL *session, WT_TABLE *table) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_open_index(WT_SESSION_IMPL *session, WT_TABLE *table, const char *idxname, size_t len, WT_INDEX **indexp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_open_indices(WT_SESSION_IMPL *session, WT_TABLE *table) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_get_colgroup(WT_SESSION_IMPL *session, const char *uri, bool quiet, WT_TABLE **tablep, WT_COLGROUP **colgroupp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_get_index(WT_SESSION_IMPL *session, const char *uri, bool quiet, WT_TABLE **tablep, WT_INDEX **indexp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_open_table(WT_SESSION_IMPL *session, const char *name, size_t namelen, bool ok_incomplete, WT_TABLE **tablep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_colcheck(WT_SESSION_IMPL *session, const char *key_format, const char *value_format, WT_CONFIG_ITEM *colconf, u_int *kcolsp, u_int *vcolsp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_table_check(WT_SESSION_IMPL *session, WT_TABLE *table) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_struct_plan(WT_SESSION_IMPL *session, WT_TABLE *table, const char *columns, size_t len, bool value_only, WT_ITEM *plan) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_struct_reformat(WT_SESSION_IMPL *session, WT_TABLE *table, const char *columns, size_t len, const char *extra_cols, bool value_only, WT_ITEM *format) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_struct_truncate(WT_SESSION_IMPL *session, const char *input_fmt, u_int ncols, WT_ITEM *format) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_project_in(WT_SESSION_IMPL *session, WT_CURSOR **cp, const char *proj_arg, va_list ap) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_project_out(WT_SESSION_IMPL *session, WT_CURSOR **cp, const char *proj_arg, va_list ap) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_project_slice(WT_SESSION_IMPL *session, WT_CURSOR **cp, const char *proj_arg, bool key_only, const char *vformat, WT_ITEM *value) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_project_merge(WT_SESSION_IMPL *session, WT_CURSOR **cp, const char *proj_arg, const char *vformat, WT_ITEM *value) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_rename(WT_SESSION_IMPL *session, const char *uri, const char *newuri, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_curstat_colgroup_init(WT_SESSION_IMPL *session, const char *uri, const char *cfg[], WT_CURSOR_STAT *cst) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_curstat_index_init(WT_SESSION_IMPL *session, const char *uri, const char *cfg[], WT_CURSOR_STAT *cst) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_curstat_table_init(WT_SESSION_IMPL *session, const char *uri, const char *cfg[], WT_CURSOR_STAT *cst) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_truncate( WT_SESSION_IMPL *session, const char *uri, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_range_truncate(WT_CURSOR *start, WT_CURSOR *stop) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_range_truncate( WT_SESSION_IMPL *session, WT_CURSOR *start, WT_CURSOR *stop) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern WT_DATA_SOURCE *__wt_schema_get_source(WT_SESSION_IMPL *session, const char *name);
-extern int __wt_str_name_check(WT_SESSION_IMPL *session, const char *str);
-extern int __wt_name_check(WT_SESSION_IMPL *session, const char *str, size_t len);
-extern int __wt_schema_worker(WT_SESSION_IMPL *session, const char *uri, int (*file_func)(WT_SESSION_IMPL *, const char *[]), int (*name_func)(WT_SESSION_IMPL *, const char *, bool *), const char *cfg[], uint32_t open_flags);
-extern int __wt_session_notsup(WT_SESSION_IMPL *session);
-extern int __wt_session_reset_cursors(WT_SESSION_IMPL *session, bool free_buffers);
-extern int __wt_session_copy_values(WT_SESSION_IMPL *session);
-extern int __wt_session_release_resources(WT_SESSION_IMPL *session);
-extern int __wt_open_cursor(WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *owner, const char *cfg[], WT_CURSOR **cursorp);
-extern int __wt_session_create( WT_SESSION_IMPL *session, const char *uri, const char *config);
-extern int __wt_session_drop(WT_SESSION_IMPL *session, const char *uri, const char *cfg[]);
-extern int __wt_session_range_truncate(WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *start, WT_CURSOR *stop);
+extern int __wt_str_name_check(WT_SESSION_IMPL *session, const char *str) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_name_check(WT_SESSION_IMPL *session, const char *str, size_t len) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_schema_worker(WT_SESSION_IMPL *session, const char *uri, int (*file_func)(WT_SESSION_IMPL *, const char *[]), int (*name_func)(WT_SESSION_IMPL *, const char *, bool *), const char *cfg[], uint32_t open_flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_session_notsup(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_session_reset_cursors(WT_SESSION_IMPL *session, bool free_buffers) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_session_copy_values(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_session_release_resources(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_open_cursor(WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *owner, const char *cfg[], WT_CURSOR **cursorp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_session_create( WT_SESSION_IMPL *session, const char *uri, const char *config) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_session_drop(WT_SESSION_IMPL *session, const char *uri, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_session_range_truncate(WT_SESSION_IMPL *session, const char *uri, WT_CURSOR *start, WT_CURSOR *stop) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern const char *__wt_session_strerror(WT_SESSION *wt_session, int error);
-extern int __wt_open_session(WT_CONNECTION_IMPL *conn, WT_EVENT_HANDLER *event_handler, const char *config, bool open_metadata, WT_SESSION_IMPL **sessionp);
-extern int __wt_open_internal_session(WT_CONNECTION_IMPL *conn, const char *name, bool open_metadata, uint32_t session_flags, WT_SESSION_IMPL **sessionp);
-extern int __wt_session_compact( WT_SESSION *wt_session, const char *uri, const char *config);
-extern int __wt_session_compact_readonly( WT_SESSION *wt_session, const char *uri, const char *config);
-extern int __wt_session_lock_dhandle( WT_SESSION_IMPL *session, uint32_t flags, bool *is_deadp);
-extern int __wt_session_release_btree(WT_SESSION_IMPL *session);
-extern int __wt_session_get_btree_ckpt(WT_SESSION_IMPL *session, const char *uri, const char *cfg[], uint32_t flags);
+extern int __wt_open_session(WT_CONNECTION_IMPL *conn, WT_EVENT_HANDLER *event_handler, const char *config, bool open_metadata, WT_SESSION_IMPL **sessionp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_open_internal_session(WT_CONNECTION_IMPL *conn, const char *name, bool open_metadata, uint32_t session_flags, WT_SESSION_IMPL **sessionp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_session_compact( WT_SESSION *wt_session, const char *uri, const char *config) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_session_compact_readonly( WT_SESSION *wt_session, const char *uri, const char *config) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_session_lock_dhandle( WT_SESSION_IMPL *session, uint32_t flags, bool *is_deadp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_session_release_btree(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_session_get_btree_ckpt(WT_SESSION_IMPL *session, const char *uri, const char *cfg[], uint32_t flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_session_close_cache(WT_SESSION_IMPL *session);
-extern int __wt_session_get_btree(WT_SESSION_IMPL *session, const char *uri, const char *checkpoint, const char *cfg[], uint32_t flags);
-extern int __wt_session_lock_checkpoint(WT_SESSION_IMPL *session, const char *checkpoint);
-extern int __wt_salvage(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_cond_auto_alloc( WT_SESSION_IMPL *session, const char *name, bool is_signalled, uint64_t min, uint64_t max, WT_CONDVAR **condp);
-extern int __wt_cond_auto_signal(WT_SESSION_IMPL *session, WT_CONDVAR *cond);
-extern int __wt_cond_auto_wait_signal( WT_SESSION_IMPL *session, WT_CONDVAR *cond, bool progress, bool *signalled);
-extern int __wt_cond_auto_wait( WT_SESSION_IMPL *session, WT_CONDVAR *cond, bool progress);
-extern int __wt_cond_auto_destroy(WT_SESSION_IMPL *session, WT_CONDVAR **condp);
-extern int __wt_decrypt(WT_SESSION_IMPL *session, WT_ENCRYPTOR *encryptor, size_t skip, WT_ITEM *in, WT_ITEM *out);
-extern int __wt_encrypt(WT_SESSION_IMPL *session, WT_KEYED_ENCRYPTOR *kencryptor, size_t skip, WT_ITEM *in, WT_ITEM *out);
+extern int __wt_session_get_btree(WT_SESSION_IMPL *session, const char *uri, const char *checkpoint, const char *cfg[], uint32_t flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_session_lock_checkpoint(WT_SESSION_IMPL *session, const char *checkpoint) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_salvage(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cond_auto_alloc( WT_SESSION_IMPL *session, const char *name, bool is_signalled, uint64_t min, uint64_t max, WT_CONDVAR **condp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cond_auto_signal(WT_SESSION_IMPL *session, WT_CONDVAR *cond) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cond_auto_wait_signal( WT_SESSION_IMPL *session, WT_CONDVAR *cond, bool progress, bool *signalled) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cond_auto_wait( WT_SESSION_IMPL *session, WT_CONDVAR *cond, bool progress) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cond_auto_destroy(WT_SESSION_IMPL *session, WT_CONDVAR **condp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_decrypt(WT_SESSION_IMPL *session, WT_ENCRYPTOR *encryptor, size_t skip, WT_ITEM *in, WT_ITEM *out) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_encrypt(WT_SESSION_IMPL *session, WT_KEYED_ENCRYPTOR *kencryptor, size_t skip, WT_ITEM *in, WT_ITEM *out) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_encrypt_size(WT_SESSION_IMPL *session, WT_KEYED_ENCRYPTOR *kencryptor, size_t incoming_size, size_t *sizep);
 extern void __wt_event_handler_set(WT_SESSION_IMPL *session, WT_EVENT_HANDLER *handler);
-extern int __wt_eventv(WT_SESSION_IMPL *session, bool msg_event, int error, const char *file_name, int line_number, const char *fmt, va_list ap);
-extern void __wt_err(WT_SESSION_IMPL *session, int error, const char *fmt, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((format (printf, 3, 4)));
-extern void __wt_errx(WT_SESSION_IMPL *session, const char *fmt, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((format (printf, 2, 3)));
-extern int __wt_ext_err_printf( WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, const char *fmt, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((format (printf, 3, 4)));
-extern int __wt_msg(WT_SESSION_IMPL *session, const char *fmt, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((format (printf, 2, 3)));
-extern int __wt_ext_msg_printf( WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, const char *fmt, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((format (printf, 3, 4)));
+extern int __wt_eventv(WT_SESSION_IMPL *session, bool msg_event, int error, const char *file_name, int line_number, const char *fmt, va_list ap) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern void __wt_err(WT_SESSION_IMPL *session, int error, const char *fmt, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((cold)) WT_GCC_FUNC_DECL_ATTRIBUTE((format (printf, 3, 4)));
+extern void __wt_errx(WT_SESSION_IMPL *session, const char *fmt, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((cold)) WT_GCC_FUNC_DECL_ATTRIBUTE((format (printf, 2, 3)));
+extern int __wt_ext_err_printf( WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, const char *fmt, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((format (printf, 3, 4))) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_msg(WT_SESSION_IMPL *session, const char *fmt, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((cold)) WT_GCC_FUNC_DECL_ATTRIBUTE((format (printf, 2, 3))) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ext_msg_printf( WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, const char *fmt, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((format (printf, 3, 4))) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern const char *__wt_ext_strerror(WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, int error);
-extern int __wt_progress(WT_SESSION_IMPL *session, const char *s, uint64_t v);
+extern int __wt_progress(WT_SESSION_IMPL *session, const char *s, uint64_t v) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void
 __wt_assert(WT_SESSION_IMPL *session,
  int error, const char *file_name, int line_number, const char *fmt, ...)
+ WT_GCC_FUNC_DECL_ATTRIBUTE((cold))
  WT_GCC_FUNC_DECL_ATTRIBUTE((format (printf, 5, 6)))
 #ifdef HAVE_DIAGNOSTIC
  WT_GCC_FUNC_DECL_ATTRIBUTE((noreturn))
 #endif
 ;
-extern int __wt_panic(WT_SESSION_IMPL *session);
-extern int __wt_illegal_value(WT_SESSION_IMPL *session, const char *name);
-extern int __wt_object_unsupported(WT_SESSION_IMPL *session, const char *uri);
-extern int __wt_bad_object_type(WT_SESSION_IMPL *session, const char *uri);
-extern int __wt_library_init(void);
-extern int __wt_breakpoint(void);
+extern int __wt_panic(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((cold)) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_illegal_value(WT_SESSION_IMPL *session, const char *name) WT_GCC_FUNC_DECL_ATTRIBUTE((cold)) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_object_unsupported(WT_SESSION_IMPL *session, const char *uri) WT_GCC_FUNC_DECL_ATTRIBUTE((cold)) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_bad_object_type(WT_SESSION_IMPL *session, const char *uri) WT_GCC_FUNC_DECL_ATTRIBUTE((cold)) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_library_init(void) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern void __wt_breakpoint(void);
 extern void __wt_attach(WT_SESSION_IMPL *session);
 extern uint64_t __wt_hash_city64(const void *s, size_t len);
 extern uint64_t __wt_hash_fnv64(const void *string, size_t len);
@@ -645,39 +646,39 @@ __wt_hazard_set(WT_SESSION_IMPL *session, WT_REF *ref, bool *busyp
  , const char *file, int line
 #endif
  );
-extern int __wt_hazard_clear(WT_SESSION_IMPL *session, WT_PAGE *page);
+extern int __wt_hazard_clear(WT_SESSION_IMPL *session, WT_PAGE *page) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_hazard_close(WT_SESSION_IMPL *session);
 extern void __wt_fill_hex(const uint8_t *src, size_t src_max, uint8_t *dest, size_t dest_max, size_t *lenp);
-extern int __wt_raw_to_hex( WT_SESSION_IMPL *session, const uint8_t *from, size_t size, WT_ITEM *to);
-extern int __wt_raw_to_esc_hex( WT_SESSION_IMPL *session, const uint8_t *from, size_t size, WT_ITEM *to);
-extern int __wt_hex2byte(const u_char *from, u_char *to);
-extern int __wt_hex_to_raw(WT_SESSION_IMPL *session, const char *from, WT_ITEM *to);
-extern int __wt_nhex_to_raw( WT_SESSION_IMPL *session, const char *from, size_t size, WT_ITEM *to);
-extern int __wt_esc_hex_to_raw(WT_SESSION_IMPL *session, const char *from, WT_ITEM *to);
-extern int __wt_huffman_open(WT_SESSION_IMPL *session, void *symbol_frequency_array, u_int symcnt, u_int numbytes, void *retp);
+extern int __wt_raw_to_hex( WT_SESSION_IMPL *session, const uint8_t *from, size_t size, WT_ITEM *to) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_raw_to_esc_hex( WT_SESSION_IMPL *session, const uint8_t *from, size_t size, WT_ITEM *to) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_hex2byte(const u_char *from, u_char *to) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_hex_to_raw(WT_SESSION_IMPL *session, const char *from, WT_ITEM *to) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_nhex_to_raw( WT_SESSION_IMPL *session, const char *from, size_t size, WT_ITEM *to) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_esc_hex_to_raw(WT_SESSION_IMPL *session, const char *from, WT_ITEM *to) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_huffman_open(WT_SESSION_IMPL *session, void *symbol_frequency_array, u_int symcnt, u_int numbytes, void *retp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_huffman_close(WT_SESSION_IMPL *session, void *huffman_arg);
-extern int __wt_print_huffman_code(void *huffman_arg, uint16_t symbol);
-extern int __wt_huffman_encode(WT_SESSION_IMPL *session, void *huffman_arg, const uint8_t *from_arg, size_t from_len, WT_ITEM *to_buf);
-extern int __wt_huffman_decode(WT_SESSION_IMPL *session, void *huffman_arg, const uint8_t *from_arg, size_t from_len, WT_ITEM *to_buf);
-extern int __wt_rwlock_alloc( WT_SESSION_IMPL *session, WT_RWLOCK **rwlockp, const char *name);
-extern int __wt_try_readlock(WT_SESSION_IMPL *session, WT_RWLOCK *rwlock);
-extern int __wt_readlock(WT_SESSION_IMPL *session, WT_RWLOCK *rwlock);
-extern int __wt_readunlock(WT_SESSION_IMPL *session, WT_RWLOCK *rwlock);
-extern int __wt_try_writelock(WT_SESSION_IMPL *session, WT_RWLOCK *rwlock);
-extern int __wt_writelock(WT_SESSION_IMPL *session, WT_RWLOCK *rwlock);
-extern int __wt_writeunlock(WT_SESSION_IMPL *session, WT_RWLOCK *rwlock);
-extern int __wt_rwlock_destroy(WT_SESSION_IMPL *session, WT_RWLOCK **rwlockp);
+extern int __wt_print_huffman_code(void *huffman_arg, uint16_t symbol) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_huffman_encode(WT_SESSION_IMPL *session, void *huffman_arg, const uint8_t *from_arg, size_t from_len, WT_ITEM *to_buf) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_huffman_decode(WT_SESSION_IMPL *session, void *huffman_arg, const uint8_t *from_arg, size_t from_len, WT_ITEM *to_buf) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_rwlock_alloc( WT_SESSION_IMPL *session, WT_RWLOCK **rwlockp, const char *name) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_try_readlock(WT_SESSION_IMPL *session, WT_RWLOCK *rwlock) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_readlock(WT_SESSION_IMPL *session, WT_RWLOCK *rwlock) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_readunlock(WT_SESSION_IMPL *session, WT_RWLOCK *rwlock) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_try_writelock(WT_SESSION_IMPL *session, WT_RWLOCK *rwlock) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_writelock(WT_SESSION_IMPL *session, WT_RWLOCK *rwlock) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_writeunlock(WT_SESSION_IMPL *session, WT_RWLOCK *rwlock) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_rwlock_destroy(WT_SESSION_IMPL *session, WT_RWLOCK **rwlockp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern uint32_t __wt_nlpo2_round(uint32_t v);
 extern uint32_t __wt_nlpo2(uint32_t v);
 extern uint32_t __wt_log2_int(uint32_t n);
 extern bool __wt_ispo2(uint32_t v);
 extern uint32_t __wt_rduppo2(uint32_t n, uint32_t po2);
 extern void __wt_random_init(WT_RAND_STATE volatile *rnd_state);
-extern int __wt_random_init_seed( WT_SESSION_IMPL *session, WT_RAND_STATE volatile *rnd_state);
+extern int __wt_random_init_seed( WT_SESSION_IMPL *session, WT_RAND_STATE volatile *rnd_state) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern uint32_t __wt_random(WT_RAND_STATE volatile *rnd_state);
-extern int __wt_buf_grow_worker(WT_SESSION_IMPL *session, WT_ITEM *buf, size_t size);
-extern int __wt_buf_fmt(WT_SESSION_IMPL *session, WT_ITEM *buf, const char *fmt, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((format (printf, 3, 4)));
-extern int __wt_buf_catfmt(WT_SESSION_IMPL *session, WT_ITEM *buf, const char *fmt, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((format (printf, 3, 4)));
+extern int __wt_buf_grow_worker(WT_SESSION_IMPL *session, WT_ITEM *buf, size_t size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_buf_fmt(WT_SESSION_IMPL *session, WT_ITEM *buf, const char *fmt, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((format (printf, 3, 4))) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_buf_catfmt(WT_SESSION_IMPL *session, WT_ITEM *buf, const char *fmt, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((format (printf, 3, 4))) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern const char *__wt_buf_set_printable( WT_SESSION_IMPL *session, const void *p, size_t size, WT_ITEM *buf);
 extern const char *__wt_buf_set_size( WT_SESSION_IMPL *session, uint64_t size, bool exact, WT_ITEM *buf);
 extern int
@@ -689,57 +690,57 @@ __wt_scr_alloc_func(WT_SESSION_IMPL *session, size_t size, WT_ITEM **scratchp
 extern void __wt_scr_discard(WT_SESSION_IMPL *session);
 extern void *__wt_ext_scr_alloc( WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, size_t size);
 extern void __wt_ext_scr_free(WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, void *p);
-extern int __wt_stat_dsrc_desc(WT_CURSOR_STAT *cst, int slot, const char **p);
+extern int __wt_stat_dsrc_desc(WT_CURSOR_STAT *cst, int slot, const char **p) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_stat_dsrc_init_single(WT_DSRC_STATS *stats);
 extern void __wt_stat_dsrc_init(WT_DATA_HANDLE *handle);
 extern void __wt_stat_dsrc_clear_single(WT_DSRC_STATS *stats);
 extern void __wt_stat_dsrc_clear_all(WT_DSRC_STATS **stats);
 extern void __wt_stat_dsrc_aggregate_single( WT_DSRC_STATS *from, WT_DSRC_STATS *to);
 extern void __wt_stat_dsrc_aggregate( WT_DSRC_STATS **from, WT_DSRC_STATS *to);
-extern int __wt_stat_connection_desc(WT_CURSOR_STAT *cst, int slot, const char **p);
+extern int __wt_stat_connection_desc(WT_CURSOR_STAT *cst, int slot, const char **p) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_stat_connection_init_single(WT_CONNECTION_STATS *stats);
 extern void __wt_stat_connection_init(WT_CONNECTION_IMPL *handle);
 extern void __wt_stat_connection_clear_single(WT_CONNECTION_STATS *stats);
 extern void __wt_stat_connection_clear_all(WT_CONNECTION_STATS **stats);
 extern void __wt_stat_connection_aggregate( WT_CONNECTION_STATS **from, WT_CONNECTION_STATS *to);
-extern int __wt_stat_join_desc(WT_CURSOR_STAT *cst, int slot, const char **p);
+extern int __wt_stat_join_desc(WT_CURSOR_STAT *cst, int slot, const char **p) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_stat_join_init_single(WT_JOIN_STATS *stats);
 extern void __wt_stat_join_clear_single(WT_JOIN_STATS *stats);
 extern void __wt_stat_join_clear_all(WT_JOIN_STATS **stats);
 extern void __wt_stat_join_aggregate( WT_JOIN_STATS **from, WT_JOIN_STATS *to);
 extern void __wt_txn_release_snapshot(WT_SESSION_IMPL *session);
-extern int __wt_txn_get_snapshot(WT_SESSION_IMPL *session);
-extern int __wt_txn_update_oldest(WT_SESSION_IMPL *session, uint32_t flags);
-extern int __wt_txn_config(WT_SESSION_IMPL *session, const char *cfg[]);
+extern int __wt_txn_get_snapshot(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_txn_update_oldest(WT_SESSION_IMPL *session, uint32_t flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_txn_config(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_txn_release(WT_SESSION_IMPL *session);
-extern int __wt_txn_commit(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_txn_rollback(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_txn_init(WT_SESSION_IMPL *session);
+extern int __wt_txn_commit(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_txn_rollback(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_txn_init(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_txn_stats_update(WT_SESSION_IMPL *session);
 extern void __wt_txn_destroy(WT_SESSION_IMPL *session);
-extern int __wt_txn_global_init(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_txn_global_destroy(WT_SESSION_IMPL *session);
-extern int __wt_checkpoint_get_handles(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_txn_checkpoint(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_checkpoint(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_checkpoint_sync(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_checkpoint_close(WT_SESSION_IMPL *session, bool final);
+extern int __wt_txn_global_init(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_txn_global_destroy(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_checkpoint_get_handles(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_txn_checkpoint(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_checkpoint(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_checkpoint_sync(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_checkpoint_close(WT_SESSION_IMPL *session, bool final) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern uint64_t __wt_ext_transaction_id(WT_EXTENSION_API *wt_api, WT_SESSION *wt_session);
-extern int __wt_ext_transaction_isolation_level( WT_EXTENSION_API *wt_api, WT_SESSION *wt_session);
-extern int __wt_ext_transaction_notify( WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, WT_TXN_NOTIFY *notify);
+extern int __wt_ext_transaction_isolation_level( WT_EXTENSION_API *wt_api, WT_SESSION *wt_session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_ext_transaction_notify( WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, WT_TXN_NOTIFY *notify) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern uint64_t __wt_ext_transaction_oldest(WT_EXTENSION_API *wt_api);
-extern int __wt_ext_transaction_visible( WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, uint64_t transaction_id);
+extern int __wt_ext_transaction_visible( WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, uint64_t transaction_id) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_txn_op_free(WT_SESSION_IMPL *session, WT_TXN_OP *op);
-extern int __wt_txn_log_op(WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt);
-extern int __wt_txn_log_commit(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_txn_checkpoint_logread( WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, WT_LSN *ckpt_lsn);
-extern int __wt_txn_checkpoint_log( WT_SESSION_IMPL *session, bool full, uint32_t flags, WT_LSN *lsnp);
-extern int __wt_txn_truncate_log( WT_SESSION_IMPL *session, WT_CURSOR_BTREE *start, WT_CURSOR_BTREE *stop);
-extern int __wt_txn_truncate_end(WT_SESSION_IMPL *session);
-extern int __wt_txn_printlog(WT_SESSION *wt_session, uint32_t flags);
-extern int __wt_txn_named_snapshot_begin(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_txn_named_snapshot_drop(WT_SESSION_IMPL *session, const char *cfg[]);
-extern int __wt_txn_named_snapshot_get(WT_SESSION_IMPL *session, WT_CONFIG_ITEM *nameval);
-extern int __wt_txn_named_snapshot_config(WT_SESSION_IMPL *session, const char *cfg[], bool *has_create, bool *has_drops);
-extern int __wt_txn_named_snapshot_destroy(WT_SESSION_IMPL *session);
-extern int __wt_txn_recover(WT_SESSION_IMPL *session);
+extern int __wt_txn_log_op(WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_txn_log_commit(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_txn_checkpoint_logread( WT_SESSION_IMPL *session, const uint8_t **pp, const uint8_t *end, WT_LSN *ckpt_lsn) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_txn_checkpoint_log( WT_SESSION_IMPL *session, bool full, uint32_t flags, WT_LSN *lsnp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_txn_truncate_log( WT_SESSION_IMPL *session, WT_CURSOR_BTREE *start, WT_CURSOR_BTREE *stop) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_txn_truncate_end(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_txn_printlog(WT_SESSION *wt_session, uint32_t flags) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_txn_named_snapshot_begin(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_txn_named_snapshot_drop(WT_SESSION_IMPL *session, const char *cfg[]) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_txn_named_snapshot_get(WT_SESSION_IMPL *session, WT_CONFIG_ITEM *nameval) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_txn_named_snapshot_config(WT_SESSION_IMPL *session, const char *cfg[], bool *has_create, bool *has_drops) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_txn_named_snapshot_destroy(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_txn_recover(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
diff --git a/src/include/extern_posix.h b/src/include/extern_posix.h
index 18f0914bc58..1cc29a5c70a 100644
--- a/src/include/extern_posix.h
+++ b/src/include/extern_posix.h
@@ -1,31 +1,31 @@
 /* DO NOT EDIT: automatically built by dist/s_prototypes. */
 
-extern int __wt_posix_directory_list(WT_FILE_SYSTEM *file_system, WT_SESSION *wt_session, const char *directory, const char *prefix, char ***dirlistp, uint32_t *countp);
-extern int __wt_posix_directory_list_free(WT_FILE_SYSTEM *file_system, WT_SESSION *wt_session, char **dirlist, uint32_t count);
-extern int __wt_dlopen(WT_SESSION_IMPL *session, const char *path, WT_DLH **dlhp);
-extern int __wt_dlsym(WT_SESSION_IMPL *session, WT_DLH *dlh, const char *name, bool fail, void *sym_ret);
-extern int __wt_dlclose(WT_SESSION_IMPL *session, WT_DLH *dlh);
-extern int __wt_posix_file_extend( WT_FILE_HANDLE *file_handle, WT_SESSION *wt_session, wt_off_t offset);
-extern int __wt_os_posix(WT_SESSION_IMPL *session);
-extern int __wt_getenv(WT_SESSION_IMPL *session, const char *variable, const char **envp);
-extern int __wt_posix_map(WT_FILE_HANDLE *fh, WT_SESSION *wt_session, void *mapped_regionp, size_t *lenp, void *mapped_cookiep);
-extern int __wt_posix_map_preload(WT_FILE_HANDLE *fh, WT_SESSION *wt_session, const void *map, size_t length, void *mapped_cookie);
-extern int __wt_posix_map_discard(WT_FILE_HANDLE *fh, WT_SESSION *wt_session, void *map, size_t length, void *mapped_cookie);
-extern int __wt_posix_unmap(WT_FILE_HANDLE *fh, WT_SESSION *wt_session, void *mapped_region, size_t len, void *mapped_cookie);
-extern int __wt_cond_alloc(WT_SESSION_IMPL *session, const char *name, bool is_signalled, WT_CONDVAR **condp);
-extern int __wt_cond_wait_signal( WT_SESSION_IMPL *session, WT_CONDVAR *cond, uint64_t usecs, bool *signalled);
-extern int __wt_cond_signal(WT_SESSION_IMPL *session, WT_CONDVAR *cond);
-extern int __wt_cond_destroy(WT_SESSION_IMPL *session, WT_CONDVAR **condp);
-extern int __wt_once(void (*init_routine)(void));
-extern int __wt_get_vm_pagesize(void);
+extern int __wt_posix_directory_list(WT_FILE_SYSTEM *file_system, WT_SESSION *wt_session, const char *directory, const char *prefix, char ***dirlistp, uint32_t *countp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_posix_directory_list_free(WT_FILE_SYSTEM *file_system, WT_SESSION *wt_session, char **dirlist, uint32_t count) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_dlopen(WT_SESSION_IMPL *session, const char *path, WT_DLH **dlhp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_dlsym(WT_SESSION_IMPL *session, WT_DLH *dlh, const char *name, bool fail, void *sym_ret) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_dlclose(WT_SESSION_IMPL *session, WT_DLH *dlh) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_posix_file_extend( WT_FILE_HANDLE *file_handle, WT_SESSION *wt_session, wt_off_t offset) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_os_posix(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_getenv(WT_SESSION_IMPL *session, const char *variable, const char **envp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_posix_map(WT_FILE_HANDLE *fh, WT_SESSION *wt_session, void *mapped_regionp, size_t *lenp, void *mapped_cookiep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_posix_map_preload(WT_FILE_HANDLE *fh, WT_SESSION *wt_session, const void *map, size_t length, void *mapped_cookie) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_posix_map_discard(WT_FILE_HANDLE *fh, WT_SESSION *wt_session, void *map, size_t length, void *mapped_cookie) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_posix_unmap(WT_FILE_HANDLE *fh, WT_SESSION *wt_session, void *mapped_region, size_t len, void *mapped_cookie) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cond_alloc(WT_SESSION_IMPL *session, const char *name, bool is_signalled, WT_CONDVAR **condp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cond_wait_signal( WT_SESSION_IMPL *session, WT_CONDVAR *cond, uint64_t usecs, bool *signalled) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cond_signal(WT_SESSION_IMPL *session, WT_CONDVAR *cond) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cond_destroy(WT_SESSION_IMPL *session, WT_CONDVAR **condp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_once(void (*init_routine)(void)) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_get_vm_pagesize(void) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern bool __wt_absolute_path(const char *path);
 extern const char *__wt_path_separator(void);
 extern bool __wt_has_priv(void);
 extern void __wt_stream_set_line_buffer(FILE *fp);
 extern void __wt_stream_set_no_buffer(FILE *fp);
 extern void __wt_sleep(uint64_t seconds, uint64_t micro_seconds);
-extern int __wt_thread_create(WT_SESSION_IMPL *session, wt_thread_t *tidret, WT_THREAD_CALLBACK(*func)(void *), void *arg);
-extern int __wt_thread_join(WT_SESSION_IMPL *session, wt_thread_t tid);
+extern int __wt_thread_create(WT_SESSION_IMPL *session, wt_thread_t *tidret, WT_THREAD_CALLBACK(*func)(void *), void *arg) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_thread_join(WT_SESSION_IMPL *session, wt_thread_t tid) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_thread_id(char *buf, size_t buflen);
-extern int __wt_epoch(WT_SESSION_IMPL *session, struct timespec *tsp);
+extern int __wt_epoch(WT_SESSION_IMPL *session, struct timespec *tsp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_yield(void);
diff --git a/src/include/extern_win.h b/src/include/extern_win.h
index c5c2624db2c..f34dbb270d0 100644
--- a/src/include/extern_win.h
+++ b/src/include/extern_win.h
@@ -1,32 +1,32 @@
 /* DO NOT EDIT: automatically built by dist/s_prototypes. */
 
-extern int __wt_win_directory_list(WT_FILE_SYSTEM *file_system, WT_SESSION *wt_session, const char *directory, const char *prefix, char ***dirlistp, uint32_t *countp);
-extern int __wt_win_directory_list_free(WT_FILE_SYSTEM *file_system, WT_SESSION *wt_session, char **dirlist, uint32_t count);
-extern int __wt_dlopen(WT_SESSION_IMPL *session, const char *path, WT_DLH **dlhp);
-extern int __wt_dlsym(WT_SESSION_IMPL *session, WT_DLH *dlh, const char *name, bool fail, void *sym_ret);
-extern int __wt_dlclose(WT_SESSION_IMPL *session, WT_DLH *dlh);
-extern int __wt_win_fs_size(WT_FILE_SYSTEM *file_system, WT_SESSION *wt_session, const char *name, wt_off_t *sizep);
-extern int __wt_os_win(WT_SESSION_IMPL *session);
-extern int __wt_getenv(WT_SESSION_IMPL *session, const char *variable, const char **envp);
-extern int __wt_win_map(WT_FILE_HANDLE *file_handle, WT_SESSION *wt_session, void *mapped_regionp, size_t *lenp, void *mapped_cookiep);
-extern int __wt_win_unmap(WT_FILE_HANDLE *file_handle, WT_SESSION *wt_session, void *mapped_region, size_t length, void *mapped_cookie);
-extern int __wt_cond_alloc(WT_SESSION_IMPL *session, const char *name, bool is_signalled, WT_CONDVAR **condp);
-extern int __wt_cond_wait_signal( WT_SESSION_IMPL *session, WT_CONDVAR *cond, uint64_t usecs, bool *signalled);
-extern int __wt_cond_signal(WT_SESSION_IMPL *session, WT_CONDVAR *cond);
-extern int __wt_cond_destroy(WT_SESSION_IMPL *session, WT_CONDVAR **condp);
-extern int __wt_once(void (*init_routine)(void));
-extern int __wt_get_vm_pagesize(void);
+extern int __wt_win_directory_list(WT_FILE_SYSTEM *file_system, WT_SESSION *wt_session, const char *directory, const char *prefix, char ***dirlistp, uint32_t *countp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_win_directory_list_free(WT_FILE_SYSTEM *file_system, WT_SESSION *wt_session, char **dirlist, uint32_t count) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_dlopen(WT_SESSION_IMPL *session, const char *path, WT_DLH **dlhp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_dlsym(WT_SESSION_IMPL *session, WT_DLH *dlh, const char *name, bool fail, void *sym_ret) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_dlclose(WT_SESSION_IMPL *session, WT_DLH *dlh) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_win_fs_size(WT_FILE_SYSTEM *file_system, WT_SESSION *wt_session, const char *name, wt_off_t *sizep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_os_win(WT_SESSION_IMPL *session) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_getenv(WT_SESSION_IMPL *session, const char *variable, const char **envp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_win_map(WT_FILE_HANDLE *file_handle, WT_SESSION *wt_session, void *mapped_regionp, size_t *lenp, void *mapped_cookiep) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_win_unmap(WT_FILE_HANDLE *file_handle, WT_SESSION *wt_session, void *mapped_region, size_t length, void *mapped_cookie) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cond_alloc(WT_SESSION_IMPL *session, const char *name, bool is_signalled, WT_CONDVAR **condp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cond_wait_signal( WT_SESSION_IMPL *session, WT_CONDVAR *cond, uint64_t usecs, bool *signalled) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cond_signal(WT_SESSION_IMPL *session, WT_CONDVAR *cond) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_cond_destroy(WT_SESSION_IMPL *session, WT_CONDVAR **condp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_once(void (*init_routine)(void)) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_get_vm_pagesize(void) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern bool __wt_absolute_path(const char *path);
 extern const char *__wt_path_separator(void);
 extern bool __wt_has_priv(void);
 extern void __wt_stream_set_line_buffer(FILE *fp);
 extern void __wt_stream_set_no_buffer(FILE *fp);
 extern void __wt_sleep(uint64_t seconds, uint64_t micro_seconds);
-extern int __wt_thread_create(WT_SESSION_IMPL *session, wt_thread_t *tidret, WT_THREAD_CALLBACK(*func)(void *), void *arg);
-extern int __wt_thread_join(WT_SESSION_IMPL *session, wt_thread_t tid);
+extern int __wt_thread_create(WT_SESSION_IMPL *session, wt_thread_t *tidret, WT_THREAD_CALLBACK(*func)(void *), void *arg) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_thread_join(WT_SESSION_IMPL *session, wt_thread_t tid) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_thread_id(char *buf, size_t buflen);
-extern int __wt_epoch(WT_SESSION_IMPL *session, struct timespec *tsp);
+extern int __wt_epoch(WT_SESSION_IMPL *session, struct timespec *tsp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern DWORD __wt_getlasterror(void);
-extern int __wt_map_windows_error(DWORD windows_error);
+extern int __wt_map_windows_error(DWORD windows_error) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern const char *__wt_formatmessage(WT_SESSION_IMPL *session, DWORD windows_error);
 extern void __wt_yield(void);
diff --git a/src/include/misc.h b/src/include/misc.h
index 1121b7dfa75..83e238b0529 100644
--- a/src/include/misc.h
+++ b/src/include/misc.h
@@ -11,6 +11,11 @@
  * and unused function return values.
  */
 #define	WT_UNUSED(var)		(void)(var)
+#define	WT_IGNORE_RET(call) do {					\
+	int __ignored_ret;						\
+	__ignored_ret = (call);						\
+	WT_UNUSED(__ignored_ret);					\
+} while (0)
 
 #define	WT_DIVIDER	"=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-="
 
diff --git a/src/include/misc.i b/src/include/misc.i
index eaa7a328ff1..93887e413a4 100644
--- a/src/include/misc.i
+++ b/src/include/misc.i
@@ -52,6 +52,7 @@ __wt_seconds(WT_SESSION_IMPL *session, time_t *timep)
 static inline int
 __wt_verbose(WT_SESSION_IMPL *session, int flag, const char *fmt, ...)
     WT_GCC_FUNC_ATTRIBUTE((format (printf, 2, 3)))
+    WT_GCC_FUNC_ATTRIBUTE((cold))
 {
 #ifdef HAVE_VERBOSE
 	WT_DECL_RET;
diff --git a/src/log/log_slot.c b/src/log/log_slot.c
index 47071211450..578085eb9be 100644
--- a/src/log/log_slot.c
+++ b/src/log/log_slot.c
@@ -262,7 +262,7 @@ __wt_log_slot_new(WT_SESSION_IMPL *session)
 		/*
 		 * If we didn't find any free slots signal the worker thread.
 		 */
-		(void)__wt_cond_auto_signal(session, conn->log_wrlsn_cond);
+		WT_RET(__wt_cond_auto_signal(session, conn->log_wrlsn_cond));
 		__wt_yield();
 	}
 	/* NOTREACHED */
diff --git a/src/lsm/lsm_tree.c b/src/lsm/lsm_tree.c
index 2ecfb614eee..a684a633fff 100644
--- a/src/lsm/lsm_tree.c
+++ b/src/lsm/lsm_tree.c
@@ -1028,7 +1028,7 @@ err:	if (locked)
 		WT_TRET(__wt_lsm_tree_writeunlock(session, lsm_tree));
 	if (ret != 0) {
 		if (chunk != NULL) {
-			(void)__wt_schema_drop(session, chunk->uri, NULL);
+			WT_TRET(__wt_schema_drop(session, chunk->uri, NULL));
 			__wt_free(session, chunk);
 		}
 		/*
diff --git a/src/support/err.c b/src/support/err.c
index 60fc53cecd0..0be428602bc 100644
--- a/src/support/err.c
+++ b/src/support/err.c
@@ -314,6 +314,7 @@ __wt_eventv(WT_SESSION_IMPL *session, bool msg_event, int error,
  */
 void
 __wt_err(WT_SESSION_IMPL *session, int error, const char *fmt, ...)
+    WT_GCC_FUNC_ATTRIBUTE((cold))
     WT_GCC_FUNC_ATTRIBUTE((format (printf, 3, 4)))
 {
 	va_list ap;
@@ -323,7 +324,7 @@ __wt_err(WT_SESSION_IMPL *session, int error, const char *fmt, ...)
 	 * an error value to return.
 	 */
 	va_start(ap, fmt);
-	(void)__wt_eventv(session, false, error, NULL, 0, fmt, ap);
+	WT_IGNORE_RET(__wt_eventv(session, false, error, NULL, 0, fmt, ap));
 	va_end(ap);
 }
 
@@ -333,6 +334,7 @@ __wt_err(WT_SESSION_IMPL *session, int error, const char *fmt, ...)
  */
 void
 __wt_errx(WT_SESSION_IMPL *session, const char *fmt, ...)
+    WT_GCC_FUNC_ATTRIBUTE((cold))
     WT_GCC_FUNC_ATTRIBUTE((format (printf, 2, 3)))
 {
 	va_list ap;
@@ -342,7 +344,7 @@ __wt_errx(WT_SESSION_IMPL *session, const char *fmt, ...)
 	 * an error value to return.
 	 */
 	va_start(ap, fmt);
-	(void)__wt_eventv(session, false, 0, NULL, 0, fmt, ap);
+	WT_IGNORE_RET(__wt_eventv(session, false, 0, NULL, 0, fmt, ap));
 	va_end(ap);
 }
 
@@ -398,6 +400,7 @@ info_msg(WT_SESSION_IMPL *session, const char *fmt, va_list ap)
  */
 int
 __wt_msg(WT_SESSION_IMPL *session, const char *fmt, ...)
+    WT_GCC_FUNC_ATTRIBUTE((cold))
     WT_GCC_FUNC_ATTRIBUTE((format (printf, 2, 3)))
 {
 	WT_DECL_RET;
@@ -474,6 +477,7 @@ __wt_progress(WT_SESSION_IMPL *session, const char *s, uint64_t v)
 void
 __wt_assert(WT_SESSION_IMPL *session,
     int error, const char *file_name, int line_number, const char *fmt, ...)
+    WT_GCC_FUNC_ATTRIBUTE((cold))
     WT_GCC_FUNC_ATTRIBUTE((format (printf, 5, 6)))
 #ifdef HAVE_DIAGNOSTIC
     WT_GCC_FUNC_ATTRIBUTE((noreturn))
@@ -482,8 +486,8 @@ __wt_assert(WT_SESSION_IMPL *session,
 	va_list ap;
 
 	va_start(ap, fmt);
-	(void)__wt_eventv(
-	    session, false, error, file_name, line_number, fmt, ap);
+	WT_IGNORE_RET(__wt_eventv(
+	    session, false, error, file_name, line_number, fmt, ap));
 	va_end(ap);
 
 #ifdef HAVE_DIAGNOSTIC
@@ -498,6 +502,7 @@ __wt_assert(WT_SESSION_IMPL *session,
  */
 int
 __wt_panic(WT_SESSION_IMPL *session)
+    WT_GCC_FUNC_ATTRIBUTE((cold))
 {
 	F_SET(S2C(session), WT_CONN_PANIC);
 	__wt_err(session, WT_PANIC, "the process must exit and restart");
@@ -521,6 +526,7 @@ __wt_panic(WT_SESSION_IMPL *session)
  */
 int
 __wt_illegal_value(WT_SESSION_IMPL *session, const char *name)
+    WT_GCC_FUNC_ATTRIBUTE((cold))
 {
 	__wt_errx(session, "%s%s%s",
 	    name == NULL ? "" : name, name == NULL ? "" : ": ",
@@ -541,6 +547,7 @@ __wt_illegal_value(WT_SESSION_IMPL *session, const char *name)
  */
 int
 __wt_object_unsupported(WT_SESSION_IMPL *session, const char *uri)
+    WT_GCC_FUNC_ATTRIBUTE((cold))
 {
 	WT_RET_MSG(session, ENOTSUP, "unsupported object operation: %s", uri);
 }
@@ -552,6 +559,7 @@ __wt_object_unsupported(WT_SESSION_IMPL *session, const char *uri)
  */
 int
 __wt_bad_object_type(WT_SESSION_IMPL *session, const char *uri)
+    WT_GCC_FUNC_ATTRIBUTE((cold))
 {
 	if (WT_PREFIX_MATCH(uri, "backup:") ||
 	    WT_PREFIX_MATCH(uri, "colgroup:") ||
diff --git a/src/support/global.c b/src/support/global.c
index eba88bf2b20..325666b1471 100644
--- a/src/support/global.c
+++ b/src/support/global.c
@@ -61,7 +61,7 @@ __wt_global_once(void)
 
 #ifdef HAVE_DIAGNOSTIC
 	/* Load debugging code the compiler might optimize out. */
-	(void)__wt_breakpoint();
+	__wt_breakpoint();
 #endif
 }
 
@@ -97,10 +97,14 @@ __wt_library_init(void)
  * __wt_breakpoint --
  *	A simple place to put a breakpoint, if you need one.
  */
-int
+void
 __wt_breakpoint(void)
 {
-	return (0);
+	/*
+	 * Yield the processor (just to keep the compiler from optimizing the
+	 * function out).
+	 */
+	__wt_yield();
 }
 
 /*
diff --git a/src/utilities/util.h b/src/utilities/util.h
index 3882d814e3a..c2cf6c22aa4 100644
--- a/src/utilities/util.h
+++ b/src/utilities/util.h
@@ -33,7 +33,8 @@ void	 util_copyright(void);
 int	 util_create(WT_SESSION *, int, char *[]);
 int	 util_drop(WT_SESSION *, int, char *[]);
 int	 util_dump(WT_SESSION *, int, char *[]);
-int	 util_err(WT_SESSION *, int, const char *, ...);
+int	 util_err(WT_SESSION *, int, const char *, ...)
+	    WT_GCC_FUNC_DECL_ATTRIBUTE((format (printf, 3, 4)));
 int	 util_flush(WT_SESSION *, const char *);
 int	 util_list(WT_SESSION *, int, char *[]);
 int	 util_load(WT_SESSION *, int, char *[]);
diff --git a/src/utilities/util_list.c b/src/utilities/util_list.c
index c7afea04b1c..57062b9e9b5 100644
--- a/src/utilities/util_list.c
+++ b/src/utilities/util_list.c
@@ -67,33 +67,29 @@ list_get_allocsize(WT_SESSION *session, const char *key, size_t *allocsize)
 	WT_CONFIG_PARSER *parser;
 	WT_DECL_RET;
 	WT_EXTENSION_API *wt_api;
+	int tret;
 	char *config;
 
 	wt_api = session->connection->get_extension_api(session->connection);
-	if ((ret =
-	    wt_api->metadata_search(wt_api, session, key, &config)) != 0) {
-		fprintf(stderr, "%s: %s: extension_api.metadata_search: %s\n",
-		    progname, key, session->strerror(session, ret));
-		return (ret);
-	}
+	if ((ret = wt_api->metadata_search(wt_api, session, key, &config)) != 0)
+		return (util_err(
+		    session, ret, "%s: WT_EXTENSION_API.metadata_search", key));
 	if ((ret = wt_api->config_parser_open(wt_api, session, config,
-	    strlen(config), &parser)) != 0) {
-		fprintf(stderr, "%s: extension_api.config_parser_open: %s\n",
-		    progname, session->strerror(session, ret));
-		return (ret);
-	}
+	    strlen(config), &parser)) != 0)
+		return (util_err(
+		    session, ret, "WT_EXTENSION_API.config_parser_open"));
 	if ((ret = parser->get(parser, "allocation_size", &szvalue)) != 0) {
-		if (ret != WT_NOTFOUND)
-			fprintf(stderr, "%s: config_parser.get: %s\n",
-			    progname, session->strerror(session, ret));
-		(void)parser->close(parser);
-		return (ret);
-	}
-	if ((ret = parser->close(parser)) != 0) {
-		fprintf(stderr, "%s: config_parser.close: %s\n",
-		    progname, session->strerror(session, ret));
+		if (ret == WT_NOTFOUND) {
+			*allocsize = 0;
+			ret = 0;
+		} else
+			ret = util_err(session, ret, "WT_CONFIG_PARSER.get");
+		if ((tret = parser->close(parser)) != 0)
+			(void)util_err(session, tret, "WT_CONFIG_PARSER.close");
 		return (ret);
 	}
+	if ((ret = parser->close(parser)) != 0)
+		return (util_err(session, ret, "WT_CONFIG_PARSER.close"));
 	*allocsize = (size_t)szvalue.val;
 	return (0);
 }
@@ -120,9 +116,8 @@ list_print(WT_SESSION *session, const char *name, bool cflag, bool vflag)
 		if (ret == ENOENT)
 			return (0);
 
-		fprintf(stderr, "%s: %s: session.open_cursor: %s\n",
-		    progname, WT_METADATA_URI, session->strerror(session, ret));
-		return (1);
+		return (util_err(session,
+		    ret, "%s: WT_SESSION.open_cursor", WT_METADATA_URI));
 	}
 
 	found = name == NULL;
@@ -196,12 +191,8 @@ list_print_checkpoint(WT_SESSION *session, const char *key)
 		return (ret == WT_NOTFOUND ? 0 : ret);
 
 	/* We need the allocation size for decoding the checkpoint addr */
-	if ((ret = list_get_allocsize(session, key, &allocsize)) != 0) {
-		if (ret == WT_NOTFOUND)
-			allocsize = 0;
-		else
-			return (ret);
-	}
+	if ((ret = list_get_allocsize(session, key, &allocsize)) != 0)
+		return (ret);
 
 	/* Find the longest name, so we can pretty-print. */
 	len = 0;
@@ -214,8 +205,7 @@ list_print_checkpoint(WT_SESSION *session, const char *key)
 	WT_CKPT_FOREACH(ckptbase, ckpt) {
 		if (allocsize != 0 && (ret = __wt_block_ckpt_decode(
 		    session, allocsize, ckpt->raw.data, &ci)) != 0) {
-			fprintf(stderr, "%s: __wt_block_buffer_to_ckpt: %s\n",
-			    progname, session->strerror(session, ret));
+			(void)util_err(session, ret, "__wt_block_ckpt_decode");
 			/* continue if damaged */
 			ci.root_size = 0;
 		}
diff --git a/src/utilities/util_misc.c b/src/utilities/util_misc.c
index 3c4e8d2dfa1..0905bfa97be 100644
--- a/src/utilities/util_misc.c
+++ b/src/utilities/util_misc.c
@@ -141,11 +141,14 @@ util_flush(WT_SESSION *session, const char *uri)
 		return (util_err(session, errno, NULL));
 
 	(void)snprintf(buf, len, "target=(\"%s\")", uri);
-	if ((ret = session->checkpoint(session, buf)) != 0) {
-		ret = util_err(session, ret, "%s: session.checkpoint", uri);
-		(void)session->drop(session, uri, NULL);
-	}
-
+	ret = session->checkpoint(session, buf);
 	free(buf);
-	return (ret);
+
+	if (ret == 0)
+		return (0);
+
+	(void)util_err(session, ret, "%s: session.checkpoint", uri);
+	if ((ret = session->drop(session, uri, NULL)) != 0)
+		(void)util_err(session, ret, "%s: session.drop", uri);
+	return (1);
 }
diff --git a/test/thread/rw.c b/test/thread/rw.c
index 10f13b9eb04..c6107a06c49 100644
--- a/test/thread/rw.c
+++ b/test/thread/rw.c
@@ -175,8 +175,8 @@ reader_op(WT_SESSION *session, WT_CURSOR *cursor, INFO *s)
 	if ((ret = cursor->search(cursor)) != 0 && ret != WT_NOTFOUND)
 		testutil_die(ret, "cursor.search");
 	if (log_print)
-		(void)session->log_printf(session,
-		    "Reader Thread %p key %017u", pthread_self(), keyno);
+		testutil_check(session->log_printf(session,
+		    "Reader Thread %p key %017u", pthread_self(), keyno));
 }
 
 /*
@@ -276,8 +276,8 @@ writer_op(WT_SESSION *session, WT_CURSOR *cursor, INFO *s)
 			testutil_die(ret, "cursor.update");
 	}
 	if (log_print)
-		(void)session->log_printf(session,
-		    "Writer Thread %p key %017u", pthread_self(), keyno);
+		testutil_check(session->log_printf(session,
+		    "Writer Thread %p key %017u", pthread_self(), keyno));
 }
 
 /*