Re: [PATCH v4] glibcextract.py: Add compile_c_snippet

[Adhemerval Zanella Netto <adhemerval.zanella@linaro.org>]

On 11/08/22 11:54, Florian Weimer wrote:
> * Adhemerval Zanella:
> 
>> It might be used on tests to check if a snippet build with the provided
>> compiler and flags.
>> ---
>>  scripts/glibcextract.py | 18 ++++++++++++++++++
>>  1 file changed, 18 insertions(+)
>>
>> diff --git a/scripts/glibcextract.py b/scripts/glibcextract.py
>> index 43ab58ffe2..33463087da 100644
>> --- a/scripts/glibcextract.py
>> +++ b/scripts/glibcextract.py
>> @@ -17,6 +17,7 @@
>>  # License along with the GNU C Library; if not, see
>>  # <https://www.gnu.org/licenses/>.
>>  
>> +import collections
>>  import os.path
>>  import re
>>  import subprocess
>> @@ -173,3 +174,20 @@ def compare_macro_consts(source_1, source_2, cc, macro_re, exclude_re=None,
>>              if not allow_extra_2:
>>                  ret = 1
>>      return ret
>> +
>> +CompileResult = collections.namedtuple("CompileResult", "returncode output")
>> +
>> +def compile_c_snippet(snippet, cc, extra_cc_args=''):
>> +    """Compile and return whether the SNIPPET can be build with CC along
>> +       EXTRA_CC_ARGS compiler flags.  Return a CompileResult with RETURNCODE
>> +       being 0 for success, or the failure value and the compiler output.
>> +    """
>> +    with tempfile.TemporaryDirectory() as temp_dir:
>> +        c_file_name = os.path.join(temp_dir, 'test.c')
>> +        obj_file_name = os.path.join(temp_dir, 'test.o')
>> +        with open(c_file_name, 'w') as c_file:
>> +            c_file.write(snippet + '\n')
>> +        cmd = cc.split() + extra_cc_args.split() + ['-c', '-o', obj_file_name,
>> +                c_file_name]
>> +        r = subprocess.run(cmd, capture_output=True)
>> +        return CompileResult(r.returncode, r.stderr)
> 
> Meh.
> 
> Traceback (most recent call last):
>   File "../sysdeps/unix/sysv/linux/tst-mount-compile.py", line 66, in <module>
>     main()
>   File "../sysdeps/unix/sysv/linux/tst-mount-compile.py", line 38, in main
>     args.cc).returncode != 0:
>   File "/home/bmg/src/glibc/scripts/glibcextract.py", line 192, in compile_c_snippet
>     r = subprocess.run(cmd, capture_output=True)
>   File "/usr/lib64/python3.6/subprocess.py", line 423, in run
>     with Popen(*popenargs, **kwargs) as process:
> TypeError: __init__() got an unexpected keyword argument 'capture_output'
> 
> That's with Python 3.6.

Sigh, it was added on Python 3.7. We will need to use stderr=PIPE instead.