gh-127076: Disable strace tests under LD_PRELOAD

[cmaloney]

Distribution tooling (ex. sandbox on Gentoo and fakeroot on Debian) uses LD_PRELOAD to intercept system calls and potentially modify them when building. These tools can change the set of system calls, so disable system call testing under these cases.

$ fakeroot ./python -m test.test_fileio -vvv CAutoFileTests.test_syscalls_read
test_syscalls_read (__main__.CAutoFileTests.test_syscalls_read)
Check that the set of system calls produced by the I/O stack is what ... skipped 'Not supported when LD_PRELOAD is intercepting system calls.'

----------------------------------------------------------------------
Ran 1 test in 0.000s

OK (skipped=1)

cc: @mgorny this should fix the Gentoo sandbox case (just disables the test). mmap used for memory allocation will be a different PR.

• Issue: FileIO Strace test fails on Gentoo (test_fileio test_syscalls_read)  #127076

[mgorny]

Thanks. This is pretty much what I did here locally, so 👍 from me.

[vstinner]

Merged, thanks.

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot aarch64 Fedora Stable Clang 3.x has failed when building commit ff2278e.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/#/builders/234/builds/6611) and take a look at the build logs.
4. Check if the failure is related to this commit (ff2278e) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/#/builders/234/builds/6611

Failed tests:

• test_interpreters

Summary of the results of the build (if available):

==

Click to see traceback logs

Traceback (most recent call last):
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-aarch64.clang/build/Lib/threading.py", line 1041, in _bootstrap_inner
    self.run()
    ~~~~~~~~^^
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-aarch64.clang/build/Lib/threading.py", line 992, in run
    self._target(*self._args, **self._kwargs)
    ~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-aarch64.clang/build/Lib/test/test_interpreters/test_stress.py", line 30, in task
    interp = interpreters.create()
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-aarch64.clang/build/Lib/test/support/interpreters/__init__.py", line 76, in create
    id = _interpreters.create(reqrefs=True)
interpreters.InterpreterError: interpreter creation failed
k


Traceback (most recent call last):
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-aarch64.clang/build/Lib/threading.py", line 1041, in _bootstrap_inner
    self.run()
    ~~~~~~~~^^
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-aarch64.clang/build/Lib/threading.py", line 992, in run
    self._target(*self._args, **self._kwargs)
    ~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-aarch64.clang/build/Lib/test/test_interpreters/test_stress.py", line 47, in run
    interp = interpreters.create()
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-aarch64.clang/build/Lib/test/support/interpreters/__init__.py", line 76, in create
    id = _interpreters.create(reqrefs=True)
interpreters.InterpreterError: interpreter creation failed
k

[cmaloney]

Bot failure is independent of this change (Failure to import encodings in interpreters test). Someday I'll manage a issue from end to end without Buildbot failure... Closer at least :)