+#ifdef MALLOC_PREFIX
+
+#define malloc AV_JOIN(MALLOC_PREFIX, malloc)
+#define memalign AV_JOIN(MALLOC_PREFIX, memalign)
+#define posix_memalign AV_JOIN(MALLOC_PREFIX, posix_memalign)
+#define realloc AV_JOIN(MALLOC_PREFIX, realloc)
+#define free AV_JOIN(MALLOC_PREFIX, free)
+
+void *malloc(size_t size);
+void *memalign(size_t align, size_t size);
+int posix_memalign(void **ptr, size_t align, size_t size);
+void *realloc(void *ptr, size_t size);
+void free(void *ptr);