strerror is now thread safe

[andrew-aitchison]

Before glibc 2.32, strerror() is not MT-Safe.
(from man strerror on Ubuntu 26.04).

glibc 2.32 was released on 2020-08-05 and glibc 2.43 on 2026-01-24
(from https://sourceware.org/glibc/wiki/Glibc%20Timeline)

This patch stops the threadsafety.py addon from warning about strerror().

strerror was used in test/cli/other_test.py to test threadsafety.py so we also patch that to use a different thread-unsafe function.

[andrew-aitchison]

I don't think the failing check reached my code. Can I run it again ?

[danmar]

This page:
https://en.cppreference.com/c/string/byte/strerror

Says:
"strerror is not required to be thread-safe"

[andrew-aitchison]

Hmm.
That is a change of spec since:
https://sourceforge.net/p/cppcheck/discussion/general/thread/209919289c/#2bf5

Spontanously I am skeptic about this warning. This warning will not age well if we keep it. In couple of years no recent distro will be unsafe.

How hard do we wish to work to avoid false-positives ?

I don't know whether other platforms have similar man-pages that could be used to generate a list for each platform. That might allow us to ship multiple lists and let the user select which ones they wish to be warned about ?

On the other hand; are how important is it to find POSIX issues as well C/C++ problems in user's code ?