From: Ivan Maidanski <ivmai@mail.ru>
Date: Mon, 28 Dec 2015 14:49:54 +0000 (+0300)
Subject: Workaround 'comparison is always false' GCC warning in GC_FAST_MALLOC_GRANS
X-Git-Tag: gc7_4_4~57
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=9b7dd43f00cb495297f40992a147424b45e2205c;p=gc

Workaround 'comparison is always false' GCC warning in GC_FAST_MALLOC_GRANS

* include/gc_inline.h (GC_FAST_MALLOC_GRANS): Refactoring of condition
expression for entry containing counter or is NULL to avoid
"comparison of unsigned expression < 0 is always false" warning
reported by GCC.
---

diff --git a/include/gc_inline.h b/include/gc_inline.h
index 8d93f44a..90a7a761 100644
--- a/include/gc_inline.h
+++ b/include/gc_inline.h
@@ -79,7 +79,7 @@ GC_API void GC_CALL GC_generic_malloc_many(size_t /* lb */, int /* k */,
         while (GC_EXPECT((GC_word)my_entry \
                         <= (num_direct) + GC_TINY_FREELISTS + 1, 0)) { \
             /* Entry contains counter or NULL */ \
-            if ((GC_word)my_entry - 1 < (num_direct)) { \
+            if ((GC_word)my_entry <= (num_direct) && my_entry != 0) { \
                 /* Small counter value, not NULL */ \
                 *my_fl = (char *)my_entry + (granules) + 1; \
                 result = (default_expr); \