Crashes after upgrading to GMP 6.20+
tg at gmplib.org
Tue Apr 27 08:19:23 UTC 2021
Michael Maroszek <paresy at gmail.com> writes:
i am using an unpatched gmplib version and the problem was introduced with
version 6.20 (still exists in 6.21). Reverting to 6.1.2 solves the problem.
There are no GMP versions 6.20 or 6.21. Are these PHP releases, perhaps?
The problem does not happen on all systems. Only a few users are affected,
which use a specific NAS (and therefore CPU). Our app is running inside a
docker container and there seems to be at least one related bug report on
The affected CPU is: Intel Celeron J3455
A CPU model GMP knows of. GMP matches it as goldmont.
Unfortunately i don't have a full example app yet. It happens when using
the GMP functions in PHP. If definitely required I would do the work and
create a plain c app, but as far as i have seen the crash directly happens
when using the gmp functions. (The crash always happens - it seems like the
"fat" code doesn't detect the target system properly and uses an invalid
These are guesses. I strongly suggest that you debug it.
Also, "crash" is is unnecessarily vague.
#0 Object "/usr/bin/foo", at 0x55e4ff7368d9, in __gmpz_set_str
2021-04-01T12:29:38.2070642Z checking build system type...
If it is matched as broadwell-pc-linux-gnu, somebody is lying. That's
hardly what the cpuid instruction on a J3455 returns.
Please encrypt, key id 0xC8601622
More information about the gmp-bugs