Eliminate 'buffer overflow detected' FP error in realloc_test

Issue #406 (bdwgc).

* mallocx.c (GC_realloc): Pass p to BZERO() thru an intermediate
variable of word type; add comment.

1 files changed, 5 insertions, 1 deletions

diff --git a/mallocx.c b/mallocx.c
index 0a1366a8..4e65fa09 100644
--- a/mallocx.c
+++ b/mallocx.c
@@ -146,7 +146,11 @@ GC_API void * GC_CALL GC_realloc(void * p, size_t lb)
             if (orig_sz > lb) {
               /* Clear unneeded part of object to avoid bogus pointer */
               /* tracing.                                             */
-                BZERO(((ptr_t)p) + lb, orig_sz - lb);
+                word cleared_p = (word)p;
+                        /* A workaround to avoid passing alloc_size(lb) */
+                        /* attribute associated with p to memset.       */
+
+                BZERO((ptr_t)cleared_p + lb, orig_sz - lb);
             }
             return(p);
         }