[Mesa-dev] [PATCH 07/11] Clang should warn only about unused CFLAGS and CXXFLAGS on debug builds.

[Kenneth Graunke]

On 01/11/2013 06:23 PM, Johannes Obermayr wrote:
> ---
>   configure.ac |    6 ++++++
>   1 Datei geändert, 6 Zeilen hinzugefügt(+)
>
> diff --git a/configure.ac b/configure.ac
> index 5bbcf05..3893570 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -1994,6 +1994,12 @@ dnl Restore LDFLAGS and CPPFLAGS
>   LDFLAGS="$_SAVE_LDFLAGS"
>   CPPFLAGS="$_SAVE_CPPFLAGS"
>
> +dnl Clang should warn only about unused CFLAGS and CXXFLAGS on debug builds
> +if test "x$acv_mesa_CLANG" = xyes && test "x$enable_debug" = xno; then
> +    CFLAGS="$CFLAGS -Qunused-arguments"
> +    CXXFLAGS="$CXXFLAGS -Qunused-arguments"
> +fi
> +
>   dnl Add user CFLAGS and CXXFLAGS
>   cflags="$CFLAGS"
>   cxxflags="$CXXFLAGS"

I disagree - if Mesa's configure.ac is going to enable unrecognized 
flags by default, then we should suppress this all the time.  Otherwise 
it's ridiculously hard to see any useful information like warnings/errors.

If we fix Mesa's configure.ac to not enable GCC-specific options on 
Clang, then I don't think we ever want to set this (so clang will warn 
on bogus user-supplied CFLAGS).