*/
#include <sys/cdefs.h>
-__FBSDID("$FreeBSD: src/lib/libc/stdlib/reallocf.c,v 1.4 2002/03/22 21:53:10 obrien Exp $");
+__FBSDID("$FreeBSD$");
#include <stdlib.h>
void *nptr;
nptr = realloc(ptr, size);
- if (!nptr && ptr)
+
+ /*
+ * When the System V compatibility option (malloc "V" flag) is
+ * in effect, realloc(ptr, 0) frees the memory and returns NULL.
+ * So, to avoid double free, call free() only when size != 0.
+ * realloc(ptr, 0) can't fail when ptr != NULL.
+ */
+ if (!nptr && ptr && size != 0)
free(ptr);
return (nptr);
}