Resolve "comparison of signed and unsigned values" compiler warnings.

* allchblk.c (GC_allochblk_nth): Cast MAX_BLACK_LIST_ALLOC and
HBLKSIZE to signed_word.
* mallocx.c (GC_generic_malloc_many): Cast my_bytes_allocd to word.
* mark.c (GC_do_local_mark): Cast the result of local_top minus
local_mark_stack to word (since is non-negative).
* misc.c (GC_base): Declare sz as unsigned word.
* misc.c (GC_enable_incremental): Cast bytes_written to size_t in
comparison to len.
* obj_map.c (GC_initialize_offsets): Declare 'i' as unsigned.
* os_dep.c (GC_or_pages): Ditto.
* typd_mlc.c (GC_init_explicit_typing): Ditto.
* ptr_chck.c (GC_is_visible): Cast the result of p minus base to word.
* typd_mlc.c (GC_make_descriptor): Cast last_set_bit to word (since
non-negative) when compared to BITMAP_BITS.

8 files changed, 17 insertions, 15 deletions

diff --git a/allchblk.c b/allchblk.c
index efcc00ab..dc35bc28 100644
--- a/allchblk.c
+++ b/allchblk.c
@@ -680,14 +680,14 @@ GC_allochblk_nth(size_t sz, int kind, unsigned flags, int n,
                 }
               }
             }
-            if ( !IS_UNCOLLECTABLE(kind) &&
-                 (kind != PTRFREE || size_needed > MAX_BLACK_LIST_ALLOC)) {
+            if ( !IS_UNCOLLECTABLE(kind) && (kind != PTRFREE
+                        || size_needed > (signed_word)MAX_BLACK_LIST_ALLOC)) {
               struct hblk * lasthbp = hbp;
               ptr_t search_end = (ptr_t)hbp + size_avail - size_needed;
               signed_word orig_avail = size_avail;
-              signed_word eff_size_needed = ((flags & IGNORE_OFF_PAGE)?
-                                                HBLKSIZE
-                                                : size_needed);
+              signed_word eff_size_needed = (flags & IGNORE_OFF_PAGE) != 0 ?
+                                                (signed_word)HBLKSIZE
+                                                : size_needed;
 
 
               while ((ptr_t)lasthbp <= search_end
diff --git a/mallocx.c b/mallocx.c
index d92014c9..e5928358 100644
--- a/mallocx.c
+++ b/mallocx.c
@@ -377,7 +377,7 @@ GC_API void GC_CALL GC_generic_malloc_many(size_t lb, int k, void **result)
         my_bytes_allocd = 0;
         for (p = op; p != 0; p = obj_link(p)) {
           my_bytes_allocd += lb;
-          if (my_bytes_allocd >= HBLKSIZE) {
+          if ((word)my_bytes_allocd >= HBLKSIZE) {
             *opp = obj_link(p);
             obj_link(p) = 0;
             break;
diff --git a/mark.c b/mark.c
index 9a34082d..434bec76 100644
--- a/mark.c
+++ b/mark.c
@@ -986,7 +986,8 @@ STATIC void GC_do_local_mark(mse *local_mark_stack, mse *local_top)
             local_top = GC_mark_from(local_top, local_mark_stack,
                                      local_mark_stack + LOCAL_MARK_STACK_SIZE);
             if (local_top < local_mark_stack) return;
-            if (local_top - local_mark_stack >= LOCAL_MARK_STACK_SIZE/2) {
+            if ((word)(local_top - local_mark_stack)
+                        >= LOCAL_MARK_STACK_SIZE / 2) {
                 GC_return_mark_stack(local_mark_stack, local_top);
                 return;
             }
diff --git a/misc.c b/misc.c
index ab3fef99..2ea209f2 100644
--- a/misc.c
+++ b/misc.c
@@ -375,7 +375,7 @@ GC_API void * GC_CALL GC_base(void * p)
         r = (ptr_t)((word)r & ~(WORDS_TO_BYTES(1) - 1));
         {
             size_t offset = HBLKDISPL(r);
-            signed_word sz = candidate_hdr -> hb_sz;
+            word sz = candidate_hdr -> hb_sz;
             size_t obj_displ = offset % sz;
 
             r -= obj_displ;
@@ -1257,7 +1257,7 @@ GC_API void GC_CALL GC_enable_incremental(void)
       IF_CANCEL(int cancel_state;)
 
       DISABLE_CANCEL(cancel_state);
-      while (bytes_written < len) {
+      while ((size_t)bytes_written < len) {
 #        ifdef GC_SOLARIS_THREADS
              result = syscall(SYS_write, fd, buf + bytes_written,
                                              len - bytes_written);
diff --git a/obj_map.c b/obj_map.c
index 082a0aa7..ed75ef12 100644
--- a/obj_map.c
+++ b/obj_map.c
@@ -78,7 +78,7 @@ GC_INNER void GC_register_displacement_inner(size_t offset)
 
 GC_INNER void GC_initialize_offsets(void)
 {
-  int i;
+  unsigned i;
   if (GC_all_interior_pointers) {
     for (i = 0; i < VALID_OFFSET_SZ; ++i)
       GC_valid_offsets[i] = TRUE;
diff --git a/os_dep.c b/os_dep.c
index 3cc6fff4..82223e9e 100644
--- a/os_dep.c
+++ b/os_dep.c
@@ -2627,7 +2627,7 @@ STATIC void GC_default_push_other_roots(void)
   /* Add all pages in pht2 to pht1 */
   STATIC void GC_or_pages(page_hash_table pht1, page_hash_table pht2)
   {
-    register int i;
+    register unsigned i;
     for (i = 0; i < PHT_SIZE; i++) pht1[i] |= pht2[i];
   }
 
diff --git a/ptr_chck.c b/ptr_chck.c
index d8076e84..5b3cc0a6 100644
--- a/ptr_chck.c
+++ b/ptr_chck.c
@@ -226,7 +226,7 @@ GC_API void * GC_CALL GC_is_visible(void *p)
                     if ((word)((ptr_t)p - (ptr_t)base) > (word)descr) goto fail;
                     break;
                 case GC_DS_BITMAP:
-                    if ((ptr_t)p - (ptr_t)base
+                    if ((word)((ptr_t)p - (ptr_t)base)
                          >= WORDS_TO_BYTES(BITMAP_BITS)
                          || ((word)p & (sizeof(word) - 1))) goto fail;
                     if (!(((word)1 << (WORDSZ - ((ptr_t)p - (ptr_t)base) - 1))
diff --git a/typd_mlc.c b/typd_mlc.c
index b031f61e..32a9b0f3 100644
--- a/typd_mlc.c
+++ b/typd_mlc.c
@@ -346,7 +346,7 @@ STATIC mse * GC_array_mark_proc(word * addr, mse * mark_stack_ptr,
 /* Caller does not hold allocation lock. */
 STATIC void GC_init_explicit_typing(void)
 {
-    register int i;
+    register unsigned i;
     DCL_LOCK_STATE;
 
     GC_STATIC_ASSERT(sizeof(struct LeafDescriptor) % sizeof(word) == 0);
@@ -540,7 +540,8 @@ GC_API GC_descr GC_CALL GC_make_descriptor(GC_bitmap bm, size_t len)
 #   define HIGH_BIT (((word)1) << (WORDSZ - 1))
 
     if (!GC_explicit_typing_initialized) GC_init_explicit_typing();
-    while (last_set_bit >= 0 && !GC_get_bit(bm, last_set_bit)) last_set_bit --;
+    while (last_set_bit >= 0 && !GC_get_bit(bm, last_set_bit))
+      last_set_bit--;
     if (last_set_bit < 0) return(0 /* no pointers */);
 #   if ALIGNMENT == CPP_WORDSZ/8
     {
@@ -557,7 +558,7 @@ GC_API GC_descr GC_CALL GC_make_descriptor(GC_bitmap bm, size_t len)
       }
     }
 #   endif
-    if (last_set_bit < BITMAP_BITS) {
+    if ((word)last_set_bit < BITMAP_BITS) {
         /* Hopefully the common case.                   */
         /* Build bitmap descriptor (with bits reversed) */
         result = HIGH_BIT;