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Diffstat (limited to 'm4/ax_check_gnu_make.m4')
| -rw-r--r-- | m4/ax_check_gnu_make.m4 | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/m4/ax_check_gnu_make.m4 b/m4/ax_check_gnu_make.m4 new file mode 100644 index 00000000000..938aad71f58 --- /dev/null +++ b/m4/ax_check_gnu_make.m4 @@ -0,0 +1,78 @@ +# =========================================================================== +# http://www.gnu.org/software/autoconf-archive/ax_check_gnu_make.html +# =========================================================================== +# +# SYNOPSIS +# +# AX_CHECK_GNU_MAKE() +# +# DESCRIPTION +# +# This macro searches for a GNU version of make. If a match is found, the +# makefile variable `ifGNUmake' is set to the empty string, otherwise it +# is set to "#". This is useful for including a special features in a +# Makefile, which cannot be handled by other versions of make. The +# variable _cv_gnu_make_command is set to the command to invoke GNU make +# if it exists, the empty string otherwise. +# +# Here is an example of its use: +# +# Makefile.in might contain: +# +# # A failsafe way of putting a dependency rule into a makefile +# $(DEPEND): +# $(CC) -MM $(srcdir)/*.c > $(DEPEND) +# +# @ifGNUmake@ ifeq ($(DEPEND),$(wildcard $(DEPEND))) +# @ifGNUmake@ include $(DEPEND) +# @ifGNUmake@ endif +# +# Then configure.in would normally contain: +# +# AX_CHECK_GNU_MAKE() +# AC_OUTPUT(Makefile) +# +# Then perhaps to cause gnu make to override any other make, we could do +# something like this (note that GNU make always looks for GNUmakefile +# first): +# +# if ! test x$_cv_gnu_make_command = x ; then +# mv Makefile GNUmakefile +# echo .DEFAULT: > Makefile ; +# echo \ $_cv_gnu_make_command \$@ >> Makefile; +# fi +# +# Then, if any (well almost any) other make is called, and GNU make also +# exists, then the other make wraps the GNU make. +# +# LICENSE +# +# Copyright (c) 2008 John Darrington <[email protected]> +# +# Copying and distribution of this file, with or without modification, are +# permitted in any medium without royalty provided the copyright notice +# and this notice are preserved. This file is offered as-is, without any +# warranty. + +#serial 7 + +AC_DEFUN([AX_CHECK_GNU_MAKE], [ AC_CACHE_CHECK( for GNU make,_cv_gnu_make_command, + _cv_gnu_make_command='' ; +dnl Search all the common names for GNU make + for a in "$MAKE" make gmake gnumake ; do + if test -z "$a" ; then continue ; fi ; + if ( sh -c "$a --version" 2> /dev/null | grep GNU 2>&1 > /dev/null ) ; then + _cv_gnu_make_command=$a ; + break; + fi + done ; + ) ; +dnl If there was a GNU version, then set @ifGNUmake@ to the empty string, '#' otherwise + if test "x$_cv_gnu_make_command" != "x" ; then + ifGNUmake='' ; + else + ifGNUmake='#' ; + AC_MSG_RESULT("Not found"); + fi + AC_SUBST(ifGNUmake) +] ) |