Fix c-analyzer for GCC: ignore LANG env var

[vstinner]

The c-analyzer doesn't support GCC localized messages, so just unset the LANG environment variable.

[vstinner]

cc @ericsnowcurrently

Example with LANG=fr_FR.UTF-8 on Fedora 38:

vstinner@mona$ make check-c-globals
python3.12 ./Tools/c-analyzer/check-c-globals.py \
	--format summary \
	--traceback
analyzing files...
.# requested file: </home/vstinner/python/main/Include/bltinmodule.h>

(...)


Traceback (most recent call last):
  (...)
  File "/home/vstinner/python/main/Tools/c-analyzer/c_parser/parser/_global.py", line 38, in parse_globals
    for srcinfo in source:
  File "/home/vstinner/python/main/Tools/c-analyzer/c_parser/parser/__init__.py", line 173, in _iter_source
    for fileinfo, line in lines:
  File "/home/vstinner/python/main/Tools/c-analyzer/c_parser/__init__.py", line 46, in <genexpr>
    srclines = ((l.file, l.data) for l in preprocessed if l.kind == 'source')
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/vstinner/python/main/Tools/c-analyzer/c_parser/preprocessor/gcc.py", line 94, in _iter_lines
    raise NotImplementedError((line, expected))
NotImplementedError: ('# 0 "<interne>"', '# 0 "<built-in>"')

make: *** [Makefile:2840: check-c-globals] Error 1

[miss-islington]

Thanks @vstinner for the PR 🌮🎉.. I'm working now to backport this PR to: 3.11, 3.12.
🐍🍒⛏🤖

[miss-islington]

Sorry @vstinner, I had trouble checking out the 3.12 backport branch.
Please retry by removing and re-adding the "needs backport to 3.12" label.
Alternatively, you can backport using cherry_picker on the command line.
cherry_picker 1f74b9e933d546a015e8497e3b8728357196acc8 3.12

[bedevere-bot]

GH-106177 is a backport of this pull request to the 3.11 branch.

[miss-islington]

Thanks @vstinner for the PR 🌮🎉.. I'm working now to backport this PR to: 3.12.
🐍🍒⛏🤖 I'm not a witch! I'm not a witch!

[bedevere-bot]

GH-106178 is a backport of this pull request to the 3.12 branch.

[gvanrossum]

I get a similar error on macOS:

.
.
.
  File "/Users/guido/cpython/Tools/c-analyzer/c_parser/__init__.py", line 46, in <genexpr>
    srclines = ((l.file, l.data) for l in preprocessed if l.kind == 'source')
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/guido/cpython/Tools/c-analyzer/c_parser/preprocessor/gcc.py", line 94, in _iter_lines
    raise NotImplementedError((line, expected))
NotImplementedError: ('# 1 "<built-in>" 1', '# 1 "<built-in>"')
make: *** [check-c-globals] Error 1

Maybe the (extremely long) message printed upon any failure ought to include the fact that it requires GCC? Or maybe it should print something simpler, like "GCC Required" when it detects a different compiler is being used? Since I only have easy access to macOS and I occasionally need to silence this tool, it's rather annoying to have to wait for a full CI cycle to validate that my guess at fixing it works.

(CC: @ericsnowcurrently, but don't interrupt your vacation for this!)

[gvanrossum]

(Also, @vstinner, thanks for the fix!)

[ericsnowcurrently]

@gvanrossum, regarding the GCC requirement, if you have a minute would you mind opening an issue for this (and CC me)? I'll probably lose track of it otherwise. Thanks! (I'm in a little village in the French Alps!)