newlength = bc + b->length - (char *)ptr;
#ifndef COMPILE_UTILITY
-if (running_in_test_harness) memset(ptr, 0xF0, newlength);
+if (running_in_test_harness)
+ {
+ (void) VALGRIND_MAKE_MEM_DEFINED(ptr, newlength);
+ memset(ptr, 0xF0, newlength);
+ }
#endif
(void) VALGRIND_MAKE_MEM_NOACCESS(ptr, newlength);
yield_length[store_pool] = newlength - (newlength % alignment);