Eliminate 'checking unsigned variable < 0' cppcheck warning in gc_inline

* include/gc_inline.h (GC_FAST_MALLOC_GRANS): Replace
(word)my_entry<=num_direct with (signed_word)my_entry-num_direct<=0
to avoid "checking unsigned var < 0" warning if num_direct==0
(no overflow is expected in (signed_word)my_entry-num_direct as it is
guaranteed that (word)my_entry<=num_direct+GC_TINY_FREELISTS+1).

diff --git a/include/gc_inline.h b/include/gc_inline.h
index 4934aee..f0d8189 100644 (file)
--- a/include/gc_inline.h
+++ b/include/gc_inline.h
@@ -121,7 +121,9 @@ GC_API GC_ATTR_MALLOC GC_ATTR_ALLOC_SIZE(1) void * GC_CALL
                 break; \
             } \
             /* Entry contains counter or NULL */ \
-            if ((GC_word)my_entry <= (num_direct) && my_entry != 0) { \
+            if ((GC_signed_word)my_entry - (GC_signed_word)(num_direct) <= 0 \
+                    /* (GC_word)my_entry <= (num_direct) */ \
+                    && my_entry != NULL) { \
                 /* Small counter value, not NULL */ \
                 *my_fl = (char *)my_entry + (granules) + 1; \
                 result = (default_expr); \