Re: RFC: Top level configure: Require a minimum version 6.8 texinfo

[Jakub Jelinek <jakub@redhat.com>]

On Tue, Aug 29, 2023 at 04:21:44PM +0100, Nick Clifton via Gcc-patches wrote:
>   Currently the top level configure.ac file sets the minimum required
>   version of texinfo to be 4.7.  I would like to propose changing this
>   to 6.8.
>   
>   The reason for the change is that the bfd documentation now needs at
>   least version 6.8 in order to build[1][2].  Given that 4.7 is now
>   almost 20 years old (it was released in April 2004), updating the
>   requirement to a newer version does seem reasonable.  On the other
>   hand 6.8 is quite new (it was released in March 2021), so a lot of
>   systems out there may not have it.
> 
>   Thoughts ?

I think that is too new.
We still allow building gcc e.g. with GCC 4.8 from ~ 10 years ago and
I think various boxes where people regularly build gcc will have similarly
old other tools.
So, bumping requirement from ~ 20 years old tools to ~ 10 years old tools
might be ok, but requiring ones at most 2 years old will be a nightmare,
especially if gcc itself doesn't have such a requirement.
Sure, we have requirements on newer gmp/mpfr/libmpc etc., but every extra
requirement means some extra work for lots of people.

So, either revert those bfd/*.texi changes, or make them somehow conditional
on the makeinfo version, or perhaps have this texinfo version requirement
only inside of bfd configure, or, if you really want to do it in toplevel
configure, make it dependent on whether bfd/ subdirectory is present (if
not, keep the old requirement, otherwise newer)?

> [1] https://sourceware.org/bugzilla/show_bug.cgi?id=30703
> [2] https://sourceware.org/pipermail/binutils/2023-February/125943.html
> 
> Suggested patch:
> 
> diff --git a/configure.ac b/configure.ac
> index 01cfd017273..10bfef1c6c5 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -3678,10 +3678,10 @@ case " $build_configdirs " in
>    *" texinfo "*) MAKEINFO='$$r/$(BUILD_SUBDIR)/texinfo/makeinfo/makeinfo' ;;
>    *)
>  changequote(,)
> -    # For an installed makeinfo, we require it to be from texinfo 4.7 or
> +    # For an installed makeinfo, we require it to be from texinfo 6.8 or
>      # higher, else we use the "missing" dummy.
>      if ${MAKEINFO} --version \
> -       | egrep 'texinfo[^0-9]*(4\.([7-9]|[1-9][0-9])|[5-9]|[1-9][0-9])' >/dev/null 2>&1; then
> +       | egrep 'texinfo[^0-9]*(6\.([8-9]|[1-9][0-9])|[7-9]|[1-9][0-9])' >/dev/null 2>&1; then
>        :
>      else
>        MAKEINFO="$MISSING makeinfo"

	Jakub