[Template merge] start requiring gnu make

m4/ax_check_gnu_make.m4

@@ -1,10 +1,10 @@
 # ===========================================================================
-#     http://www.gnu.org/software/autoconf-archive/ax_check_gnu_make.html
+#    https://www.gnu.org/software/autoconf-archive/ax_check_gnu_make.html
 # ===========================================================================
 #
 # SYNOPSIS
 #
-#   AX_CHECK_GNU_MAKE()
+#   AX_CHECK_GNU_MAKE([run-if-true],[run-if-false])
 #
 # DESCRIPTION
 #
@@ -13,13 +13,19 @@
 #     * 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 makefile variable `ifnGNUmake' is set to #, otherwise
+#       it is set to the empty string. This is useful for including a special
+#       features in a Makefile, which can be handled
+#       by other versions of make or to specify else like clause.
 #     * The variable `_cv_gnu_make_command` is set to the command to invoke
 #       GNU make if it exists, the empty string otherwise.
 #     * The variable `ax_cv_gnu_make_command` is set to the command to invoke
 #       GNU make by copying `_cv_gnu_make_command`, otherwise it is unset.
 #     * If GNU Make is found, its version is extracted from the output of
 #       `make --version` as the last field of a record of space-separated
 #       columns and saved into the variable `ax_check_gnu_make_version`.
+#     * Additionally if GNU Make is found, run shell code run-if-true
+#       else run shell code run-if-false.
 #
 #   Here is an example of its use:
 #
@@ -31,6 +37,8 @@
 #
 #     @ifGNUmake@ ifeq ($(DEPEND),$(wildcard $(DEPEND)))
 #     @ifGNUmake@ include $(DEPEND)
+#     @ifGNUmake@ else
+#     fallback code
 #     @ifGNUmake@ endif
 #
 #   Then configure.in would normally contain:
@@ -61,7 +69,7 @@
 #   and this notice are preserved. This file is offered as-is, without any
 #   warranty.
 
-#serial 8
+#serial 12
 
 AC_DEFUN([AX_CHECK_GNU_MAKE],dnl
   [AC_PROG_AWK
@@ -79,6 +87,9 @@ dnl Search all the common names for GNU make
     done ;])
 dnl If there was a GNU version, then set @ifGNUmake@ to the empty string, '#' otherwise
   AS_VAR_IF([_cv_gnu_make_command], [""], [AS_VAR_SET([ifGNUmake], ["#"])],   [AS_VAR_SET([ifGNUmake], [""])])
+  AS_VAR_IF([_cv_gnu_make_command], [""], [AS_VAR_SET([ifnGNUmake], [""])],   [AS_VAR_SET([ifnGNUmake], ["#"])])
   AS_VAR_IF([_cv_gnu_make_command], [""], [AS_UNSET(ax_cv_gnu_make_command)], [AS_VAR_SET([ax_cv_gnu_make_command], [${_cv_gnu_make_command}])])
+  AS_VAR_IF([_cv_gnu_make_command], [""],[$2],[$1])
   AC_SUBST([ifGNUmake])
+  AC_SUBST([ifnGNUmake])
 ])

m4/giella-macros.m4

@@ -274,31 +274,24 @@ AM_CONDITIONAL([CAN_MERGE], [test "x$can_merge" != xno ])
 AC_CANONICAL_HOST
 # Check for which host we are on and setup a few things
 # specifically based on the host
-# This is the minimum GNU Make version required (except on OSX):
+# This is the minimum GNU Make version required
 _GNU_make_min_version=m4_default([$1], [3.82])
 
-# Then we check against different hosts:
-case $host_os in
-  darwin* )
-        # Do nothing for mac: the included make is fine
-        true
-        ;;
-    *)
-        # Default Case: in all other cases check that we are using GNU make
-        # and that it is new enough:
-        AX_CHECK_GNU_MAKE()
-        AC_MSG_CHECKING([whether GNU make is at least $_GNU_make_min_version])
-        AX_COMPARE_VERSION([$ax_check_gnu_make_version], [ge],
-                           [$_GNU_make_min_version],
-                   [
-                    AC_MSG_RESULT([yes])
-                    # Reset the MAKE variable, to ensure we're using GNU make:
-                    MAKE=$_cv_gnu_make_command
-                   ],
-                   [AC_MSG_ERROR([GNU Make too old ($ax_check_gnu_make_version), please install at least $_GNU_make_min_version])
-                   ])
-        ;;
-esac
+AX_CHECK_GNU_MAKE(,
+                  [AC_MSG_WARN([GNU make will be required])])
+AC_MSG_CHECKING([whether GNU make is at least $_GNU_make_min_version])
+AX_COMPARE_VERSION([$ax_check_gnu_make_version], [ge],
+                   [$_GNU_make_min_version],
+           [
+            AC_MSG_RESULT([yes])
+            # Reset the MAKE variable, to ensure we're using GNU make:
+            MAKE=$_cv_gnu_make_command
+           ],
+           [AC_MSG_RESULT([no])
+            AC_MSG_WARN([GNU Make too old ($ax_check_gnu_make_version), please install at least $_GNU_make_min_version])
+            gt_need_gnu_make=yes
+           ])
+
 ################ END of GNU Make check ################
 
 # We need special treatment of Java paths in Cygwin:
@@ -1108,6 +1101,12 @@ cd ..
 git clone git@github.com:giellalt/$gt_SHARED_FAILS
 cd $gt_SHARED_FAILS
 ./autogen.sh && ./configure && make])])
+AS_IF([test "x$gt_need_gnu_make" = xyes],
+      [AC_MSG_WARN([GNU make will be required to build giellalt from now on (Feb 2025):
+
+if you are using a MacOS do:
+    sudo brew install make
+see https://github.com/giellalt/giella-core/issues/79 for background and further instructions])])
 ]) # gt_PRINT_FOOTER
 
 # vim: set ft=config: