1 # =========================================================================== 2 # http://www.gnu.org/software/autoconf-archive/ax_check_gnu_make.html 3 # =========================================================================== 4 # 5 # SYNOPSIS 6 # 7 # AX_CHECK_GNU_MAKE() 8 # 9 # DESCRIPTION 10 # 11 # This macro searches for a GNU version of make. If a match is found, the 12 # makefile variable `ifGNUmake' is set to the empty string, otherwise it 13 # is set to "#". This is useful for including a special features in a 14 # Makefile, which cannot be handled by other versions of make. The 15 # variable _cv_gnu_make_command is set to the command to invoke GNU make 16 # if it exists, the empty string otherwise. 17 # 18 # Here is an example of its use: 19 # 20 # Makefile.in might contain: 21 # 22 # # A failsafe way of putting a dependency rule into a makefile 23 # $(DEPEND): 24 # $(CC) -MM $(srcdir)/*.c > $(DEPEND) 25 # 26 # @ifGNUmake@ ifeq ($(DEPEND),$(wildcard $(DEPEND))) 27 # @ifGNUmake@ include $(DEPEND) 28 # @ifGNUmake@ endif 29 # 30 # Then configure.in would normally contain: 31 # 32 # AX_CHECK_GNU_MAKE() 33 # AC_OUTPUT(Makefile) 34 # 35 # Then perhaps to cause gnu make to override any other make, we could do 36 # something like this (note that GNU make always looks for GNUmakefile 37 # first): 38 # 39 # if ! test x$_cv_gnu_make_command = x ; then 40 # mv Makefile GNUmakefile 41 # echo .DEFAULT: > Makefile ; 42 # echo \ $_cv_gnu_make_command \$@ >> Makefile; 43 # fi 44 # 45 # Then, if any (well almost any) other make is called, and GNU make also 46 # exists, then the other make wraps the GNU make. 47 # 48 # LICENSE 49 # 50 # Copyright (c) 2008 John Darrington <j.darrington (a] elvis.murdoch.edu.au> 51 # 52 # Copying and distribution of this file, with or without modification, are 53 # permitted in any medium without royalty provided the copyright notice 54 # and this notice are preserved. This file is offered as-is, without any 55 # warranty. 56 57 #serial 7 58 59 AC_DEFUN([AX_CHECK_GNU_MAKE], [ AC_CACHE_CHECK( for GNU make,_cv_gnu_make_command, 60 _cv_gnu_make_command='' ; 61 dnl Search all the common names for GNU make 62 for a in "$MAKE" make gmake gnumake ; do 63 if test -z "$a" ; then continue ; fi ; 64 if ( sh -c "$a --version" 2> /dev/null | grep GNU 2>&1 > /dev/null ) ; then 65 _cv_gnu_make_command=$a ; 66 break; 67 fi 68 done ; 69 ) ; 70 dnl If there was a GNU version, then set @ifGNUmake@ to the empty string, '#' otherwise 71 if test "x$_cv_gnu_make_command" != "x" ; then 72 ifGNUmake='' ; 73 else 74 ifGNUmake='#' ; 75 AC_MSG_RESULT("Not found"); 76 fi 77 AC_SUBST(ifGNUmake) 78 ] ) 79
