# =========================================================================== # 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 \ $_cv_gnu_make_command \$@ >> Makefile; # fi # # Then, if any (well almost any) other make is called, and GNU make also # exists, then the other make wraps the GNU make. # # LICENSE # # Copyright (c) 2008 John Darrington <j.darrington@elvis.murdoch.edu.au> # # Copying and distribution of this file, with or without modification, are # permitted in any medium without royalty provided the copyright notice # and this notice are preserved. This file is offered as-is, without any # warranty. #serial 7 AC_DEFUN([AX_CHECK_GNU_MAKE], [ AC_CACHE_CHECK( for GNU make,_cv_gnu_make_command, _cv_gnu_make_command='' ; dnl Search all the common names for GNU make for a in "$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) ] )