Program crashes on stable/13 (but not on 12.3)

From: Peter <>
Date: Sat, 05 Mar 2022 19:26:40 UTC

 this program crashes SEGV on stable/13 after 135962 iterations,
but continues to run on 12.3.

My stable/13 is still at 22ba2970766 - if You happen to be on a
newer level, then please just try this out.

#include <unistd.h>
#include <fcntl.h>
#include <stdio.h>

main() {
    char buf[] = "12345678901234567890123456789012345678901234567890";
    int fd = open("/dev/null", O_RDONLY);
    int i = 0;

    dup2(fd, 1);

    while(1) {
      fputs(buf, stdout);
      fprintf(stderr, "%d\n", i);

I know that the code is bogus, but this is exactly what one of our
ports does (and why it started to crash after upgrading to stable/13).

And I think it should not SEGV, anyway.

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