Subject: Re: bug#58923: Malformed core dumps on Guix System

From: Ludovic Courtès <[email-masked]>
Date: Wed, 02 Nov 2022 11:31:26 +0100

Hi,

Mathieu Othacehe <[email-masked]> skribis:

> mathieu@meije ~/tmp [env]$ gdb ./a.out /tmp/my-core-5622
> ...
> BFD: warning: /tmp/my-core-5622 has a segment extending past end of file
> ...
> Failed to read a valid object file image from memory.

I never encountered that issue, although I’ve had to look a lot at core
dumps over time.  :-)

--8<---------------cut here---------------start------------->8---
$ gcc test.c
$ ulimit -c unlimited 
$ ./a.out
Segmentation fault (core dumped)
$ gdb a.out core
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Reading symbols from a.out...
(No debugging symbols found in a.out)
[New LWP 23407]
Core was generated by `./a.out'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  0x0000000000401106 in main ()
(gdb) bt
#0  0x0000000000401106 in main ()
(gdb) quit
--8<---------------cut here---------------end--------------->8---

Could it have to do with /proc/sys/kernel/core_pattern or with the fact
that your /tmp file system was full or something?  What if you try to
have the core dump on another file system?

Thanks,
Ludo’.