Re: [PATCH] Tweak language choice in config-list.mk

[Richard Biener <richard.guenther@gmail.com>]

On Thu, Sep 7, 2023 at 11:30 AM Richard Sandiford via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
> When I tried to use config-list.mk, the build for every triple except
> the build machine's failed for m2.  This is because, unlike other
> languages, m2 builds target objects during all-gcc.  The build will
> therefore fail unless you have access to an appropriate binutils
> (or an equivalent).  That's quite a big ask for over 100 targets. :)
>
> This patch therefore makes m2 an optional inclusion.
>
> Doing that wasn't entirely straightforward though.  The current
> configure line includes "--enable-languages=all,...", which means
> that the "..." can only force languages to be added that otherwise
> wouldn't have been.  (I.e. the only effect of the "..." is to
> override configure autodetection.)
>
> The choice of all,ada and:
>
>   # Make sure you have a recent enough gcc (with ada support) in your path so
>   # that --enable-werror-always will work.
>
> make it clear that lack of GNAT should be a build failure rather than
> silently ignored.  This predates the D frontend, which requires GDC
> in the same way that Ada requires GNAT.  I don't know of a reason
> why D should be treated differently.
>
> The patch therefore expands the "all" into a specific list of
> languages.
>
> That in turn meant that Fortran had to be handled specially,
> since bpf and mmix don't support Fortran.
>
> Perhaps there's an argument that m2 shouldn't build target objects
> during all-gcc,

Yes, I think that's unfortunate - can you open a bugreport for this?

> but (a) it works for practical usage and (b) the
> patch is an easy workaround.  I'd be happy for the patch to be
> reverted if the build system changes.
>
> OK to install?

OK.

> Richard
>
>
> gcc/
>         * contrib/config-list.mk (OPT_IN_LANGUAGES): New variable.
>         ($(LIST)): Replace --enable-languages=all with a specifc list.
>         Disable fortran on bpf and mmix.  Enable the languages in
>         OPT_IN_LANGUAGES.
> ---
>  contrib/config-list.mk | 17 ++++++++++++++---
>  1 file changed, 14 insertions(+), 3 deletions(-)
>
> diff --git a/contrib/config-list.mk b/contrib/config-list.mk
> index e570b13c71b..50ecb014bc0 100644
> --- a/contrib/config-list.mk
> +++ b/contrib/config-list.mk
> @@ -12,6 +12,11 @@ TEST=all-gcc
>  # supply an absolute path.
>  GCC_SRC_DIR=../../gcc
>
> +# Define this to ,m2 if you want to build Modula-2.  Modula-2 builds target
> +# objects during all-gcc, so it can only be included if you've installed
> +# binutils (or an equivalent) for each target.
> +OPT_IN_LANGUAGES=
> +
>  # Use -j / -l make arguments and nice to assure a smooth resource-efficient
>  # load on the build machine, e.g. for 24 cores:
>  # svn co svn://gcc.gnu.org/svn/gcc/branches/foo-branch gcc
> @@ -126,17 +131,23 @@ $(LIST): make-log-dir
>                 TGT=`echo $@ | awk 'BEGIN { FS = "OPT" }; { print $$1 }'` &&                    \
>                 TGT=`$(GCC_SRC_DIR)/config.sub $$TGT` &&                                        \
>                 case $$TGT in                                                                   \
> -                       *-*-darwin* | *-*-cygwin* | *-*-mingw* | *-*-aix* | bpf-*-*)                    \
> +                       bpf-*-*)                                                                \
>                                 ADDITIONAL_LANGUAGES="";                                        \
>                                 ;;                                                              \
> -                       *)                                                                      \
> +                       *-*-darwin* | *-*-cygwin* | *-*-mingw* | *-*-aix* | bpf-*-*)            \
> +                               ADDITIONAL_LANGUAGES=",fortran";                                \
> +                               ;;                                                              \
> +                       mmix-*-*)                                                               \
>                                 ADDITIONAL_LANGUAGES=",go";                                     \
>                                 ;;                                                              \
> +                       *)                                                                      \
> +                               ADDITIONAL_LANGUAGES=",fortran,go";                             \
> +                               ;;                                                              \
>                 esac &&                                                                         \
>                 $(GCC_SRC_DIR)/configure                                                        \
>                         --target=$(subst SCRIPTS,`pwd`/../scripts/,$(subst OPT,$(empty) -,$@))  \
>                         --enable-werror-always ${host_options}                                  \
> -                       --enable-languages=all,ada$$ADDITIONAL_LANGUAGES;                       \
> +                       --enable-languages=c,ada,c++,d,lto,objc,obj-c++,rust$$ADDITIONAL_LANGUAGES$(OPT_IN_LANGUAGES); \
>         ) > log/$@-config.out 2>&1
>
>  $(LOGFILES) : log/%-make.out : %
> --
> 2.25.1
>