exts.mk.tmpl: for not GNU makes

* template/exts.mk.tmpl: use `cd` then `make` instead of `make -C`
  when not GNU make.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@57438 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

common.mk

@@ -215,7 +215,7 @@ $(EXTS_MK): ext/configure-ext.mk $(TIMESTAMPDIR)/.$(arch).time $(srcdir)/templat
 		gnumake=$(gnumake) EXTLDFLAGS="$(EXTLDFLAGS)" srcdir="$(srcdir)"
 	$(ECHO) generating makefile $@
 	$(Q)$(MINIRUBY) $(srcdir)/tool/generic_erb.rb -o $@ -c \
-	    $(srcdir)/template/exts.mk.tmpl
+	    $(srcdir)/template/exts.mk.tmpl --gnumake=$(gnumake)
 
 ext/configure-ext.mk: $(PREP) all-incs $(MKFILES) $(RBCONFIG) $(LIBRUBY)
 	$(ECHO) generating makefiles $@

template/exts.mk.tmpl

@@ -9,6 +9,11 @@ require './rbconfig'
 macros = {}
 deps = []
 note = []
+gnumake = false
+opt = OptionParser.new do |o|
+  o.on('--gnumake=BOOL') {|v| gnumake = v == 'yes'}
+  o.order!(ARGV)
+end
 Dir.glob("ext/*/exts.mk") do |e|
   s = File.read(e)
   s.scan(/^(extensions|EXT[A-Z]+)[ \t]*=[ \t]*((?>(?>[^\\\n]|\\.)*\\\n)*(?>[^\\\n]|\\.)*)$/) do |n, v|
@@ -57,6 +62,13 @@ def self.column
 end
 targets = %w[all static install install-so install-rb clean distclean realclean]
 objext = RbConfig::CONFIG["OBJEXT"]
+if gnumake
+  submake = "$(MAKE) -C $(@D)"
+else
+  submake = "cd $(@D) && "
+  exec = RbConfig::CONFIG["exec"] and !exec.empty? and submake << str << " "
+  submake << "$(MAKE)"
+end
 %>
 
 extensions =<%= macros["extensions"].fold(column) %>
@@ -89,7 +101,7 @@ ext/extinit.<%=objext%>:
 
 % targets.product(macros["extensions"].map {|e|e.chomp("/.")}) do |t, e|
 <%=e%>/<%=t%>:
-	$(Q)$(MAKE) -C $(@D) $(MFLAGS) V=$(V) $(@F)
+	$(Q)<%= submake %> $(MFLAGS) $(SUBMAKEOPTS) V=$(V) $(@F)
 % end
 
 extso: