1 #include <malloc.h>
2 #include "malloc_impl.h"
3 
4 hidden void *(*const __realloc_dep)(void *, size_t) = realloc;
5 
malloc_usable_size(void *p)6 size_t malloc_usable_size(void *p)
7 {
8 	return p ? CHUNK_SIZE(MEM_TO_CHUNK(p)) - OVERHEAD : 0;
9 }
10