Bug#45288: pb2 returns a lot of compilation warnings on linux

Fix warnings flagged by the new warning option -Wunused-but-set-variable
that was added to GCC 4.6 and that is enabled by -Wunused and -Wall. The
option causes a warning whenever a local variable is assigned to but is
later unused. It also warns about meaningless pointer dereferences.

client/mysql.cc:
  Meaningless pointer dereferences.
client/mysql_upgrade.c:
  Check whether reading from the file succeeded.
extra/comp_err.c:
  Unused.
extra/yassl/src/yassl_imp.cpp:
  Skip instead of reading data that is discarded.
include/my_pthread.h:
  Variable is only used in debug builds.
include/mysys_err.h:
  Add new error messages.
mysys/errors.c:
  Add new error message for permission related functions.
mysys/mf_iocache.c:
  Variable is only checked under THREAD.
mysys/my_copy.c:
  Raise a error if chmod or chown fails.
mysys/my_redel.c:
  Raise a error if chmod or chown fails.
regex/engine.c:
  Use a equivalent variable for the assert.
server-tools/instance-manager/instance_options.cc:
  Unused.
sql/field.cc:
  Unused.
sql/item.cc:
  Unused.
sql/log.cc:
  Do not ignore the return value of freopen: only set buffer if
  reopening succeeds.
  
  Adjust doxygen comment to the right function.
  
  Pass message lenght to log function.
sql/mysqld.cc:
  Do not ignore the return value of freopen: only set buffer if
  reopening succeeds.
sql/partition_info.cc:
  Unused.
sql/slave.cc:
  No need to set pointer to the address of '\0'.
sql/spatial.cc:
  Unused. Left for historical purposes.
sql/sql_acl.cc:
  Unused.
sql/sql_base.cc:
  Pointers are always set to the same variables.
sql/sql_parse.cc:
  End statement if reading fails.
  
  Store the buffer after it has actually been updated.
sql/sql_repl.cc:
  No need to set pointer to the address of '\0'.
sql/sql_show.cc:
  Put variable under the same ifdef block.
sql/udf_example.c:
  Set null pointer flag appropriately.
storage/csv/ha_tina.cc:
  Meaningless dereferences.
storage/example/ha_example.cc:
  Return the error since it's available.
storage/myisam/mi_locking.c:
  Remove unused and dead code.

1 files changed, 11 insertions, 6 deletions

diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc
index 1f3d29ffec0..134517e5bf7 100644
--- a/sql/sql_parse.cc
+++ b/sql/sql_parse.cc
@@ -465,6 +465,12 @@ static void handle_bootstrap_impl(THD *thd)
       }
       buff= (char*) thd->net.buff;
       res= fgets(buff + length, thd->net.max_packet - length, file);
+      if (!res && !feof(file))
+      {
+        net_end_statement(thd);
+        bootstrap_error= 1;
+        break;
+      }
       length+= (ulong) strlen(buff + length);
       /* purecov: end */
     }
@@ -1535,7 +1541,7 @@ bool dispatch_command(enum enum_server_command command, THD *thd,
   {
     STATUS_VAR current_global_status_var;
     ulong uptime;
-    uint length;
+    uint length __attribute__((unused));
     ulonglong queries_per_second1000;
     char buff[250];
     uint buff_len= sizeof(buff);
@@ -1548,7 +1554,7 @@ bool dispatch_command(enum enum_server_command command, THD *thd,
     else
       queries_per_second1000= thd->query_id * LL(1000) / uptime;
 
-    length= my_snprintf((char*) buff, buff_len - 1,
+    length= my_snprintf(buff, buff_len - 1,
                         "Uptime: %lu  Threads: %d  Questions: %lu  "
                         "Slow queries: %lu  Opens: %lu  Flush tables: %lu  "
                         "Open tables: %u  Queries per second avg: %u.%u",
@@ -1560,10 +1566,6 @@ bool dispatch_command(enum enum_server_command command, THD *thd,
                         cached_open_tables(),
                         (uint) (queries_per_second1000 / 1000),
                         (uint) (queries_per_second1000 % 1000));
-#ifdef EMBEDDED_LIBRARY
-    /* Store the buffer in permanent memory */
-    my_ok(thd, 0, 0, buff);
-#endif
 #ifdef SAFEMALLOC
     if (sf_malloc_cur_memory)				// Using SAFEMALLOC
     {
@@ -1578,6 +1580,9 @@ bool dispatch_command(enum enum_server_command command, THD *thd,
     VOID(my_net_write(net, (uchar*) buff, length));
     VOID(net_flush(net));
     thd->main_da.disable_status();
+#else
+    /* Store the buffer in permanent memory */
+    my_ok(thd, 0, 0, buff);
 #endif
     break;
   }