On 13 Mar 2002, Bryan Paxton wrote:
> $ cat 2free.c
> #include <stdio.h>
> #include <stdlib.h>
>
> int main(int argc, char* argv[]) {
> void* foo = malloc(16);
> free(foo);
> free(foo);
> printf("Program ran to completion.\n");
> }
> $ export MALLOC_CHECK=2 && gcc -o 2free 2free.c && ./2free
> Segmentation fault (core dumped)
> $
Your test program is not correct as it implies undefined behaviour per the
C standard (7.20.3.2). Therefore, it's "normal" that your test program
crashes, for example. Should you had set foo = NULL prior to the
free()'ing the second time, well it will have to work then.
Bye,
Gwenole.
