[PATCH v3] glibcextract.py: Add compile_c_snippet

[Florian Weimer]

* Adhemerval Zanella:

> It might be used on tests to check if a snippet build with the provided
> compiler and flags.
> ---
>  scripts/glibcextract.py | 20 ++++++++++++++++++++
>  1 file changed, 20 insertions(+)
>
> diff --git a/scripts/glibcextract.py b/scripts/glibcextract.py
> index 43ab58ffe2..78735fad43 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 +174,22 @@ 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()
> +        if len(extra_cc_args) > 0:
> +            cmd += [extra_cc_args]
> +        cmd += ['-c', '-o', obj_file_name, c_file_name]
> +        r = subprocess.run(cmd, capture_output=True)
> +        return CompileResult(r.returncode, r.stderr)

Sadly that doesn't work because extra_cc_args isn't split.

Maybe we should just keep using the shell (without the redirect).

Thanks,
Florian