Re: [PATCH] GNUmakefile build tweaks.

[Bob Proulx]

Eric Blake wrote:
> * configure.ac: If autoconf is new enough, link GNUmakefile into VPATH
> builds.

Is there another way to determine if autoconf is new enough?

> +dnl Allow maintainer rules under GNU make even in VPATH builds.  This does
> +dnl not work in autoconf 2.61 or earlier, but we don't want to require
> +dnl non-maintainers to use unreleased autoconf, hence the version test.
> +dnl TODO remove the version check once autoconf 2.62 is released.
> +m4_if(m4_version_compare([2.61a.100], m4_defn([AC_AUTOCONF_VERSION])), [1], 
> [],
> +      [AC_CONFIG_LINKS([GNUmakefile:GNUmakefile])])
> +
>  AC_CONFIG_FILES(
>    Makefile
>    doc/Makefile

Unfortuantely using AC_AUTOCONF_VERSION breaks autoconf-2.61 which
doesn't have it.

  ./bootstrap: aclocal --force -I m4 ...
  configure.ac:340: error: m4_defn: undefined macro: AC_AUTOCONF_VERSION
  configure.ac:340: the top level
  autom4te: /usr/local/build/coreutils/bin/m4 failed with exit status: 1
  aclocal: autom4te failed with exit status: 1
  program finished with exit code 1

[Yes, we all want the lawyers to finish the release exception for the
autotools!  Argh.]

Bob