[Mesa-dev] [PATCH] configure: Don't override user -g or -O options for debug builds

[Matt Turner]

On Mon, Jul 14, 2014 at 11:49 AM, Ian Romanick <idr at freedesktop.org> wrote:
> From: Ian Romanick <ian.d.romanick at intel.com>
>
> I already pass '-ggdb3 -O1' or '-ggdb3 -Og' for CFLAGS, and I don't want
> configure to change them for me.
>
> Signed-off-by: Ian Romanick <ian.d.romanick at intel.com>
> ---
>  configure.ac | 14 ++++++++++++--
>  1 file changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/configure.ac b/configure.ac
> index 4646212..04abcc0 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -308,10 +308,20 @@ AC_ARG_ENABLE([debug],
>  if test "x$enable_debug" = xyes; then
>      DEFINES="$DEFINES -DDEBUG"
>      if test "x$GCC" = xyes; then
> -        CFLAGS="$CFLAGS -g -O0"
> +        if ! echo "$CFLAGS" | grep -q -e '-g'; then
> +            CFLAGS="$CFLAGS -g"
> +        fi
> +        if ! echo "$CFLAGS" | grep -q -e '-O'; then
> +            CFLAGS="$CFLAGS -O0"
> +        fi
>      fi
>      if test "x$GXX" = xyes; then
> -        CXXFLAGS="$CXXFLAGS -g -O0"
> +        if ! echo "$CXXFLAGS" | grep -q -e '-g'; then
> +            CXXFLAGS="$CXXFLAGS -g"
> +        fi
> +        if ! echo "$CXXFLAGS" | grep -q -e '-O'; then
> +            CXXFLAGS="$CXXFLAGS -O0"
> +        fi
>      fi
>  fi
>
> --
> 1.8.1.4

This looks like strictly an improvement, so my feedback shouldn't hold
this up, but maybe it's time to fight about whether --enable-debug
should add -O0 at all. :)

Reviewed-by: Matt Turner <mattst88 at gmail.com>

Autotools defaults are -g -O2. Some people want debug builds to use
-g, others -ggdb*. Some people want -O2 (optimize, but with assertions
enabled), others -O0, others -Og. It'd be nice to not have
--enable-debug turn on one combination of these.