mruby-config: add --cc and --ld options.

* `--cc` print compiler name
* `--ld` print linker name

mrbgems/mruby-bin-config/mruby-config

@@ -4,7 +4,9 @@ print_help()
 {
   echo "Usage: mruby-config [switches]"
   echo "  switches:"
+  echo "  --cc                        print compiler name"
   echo "  --cflags                    print flags passed to compiler"
+  echo "  --ld                        print linker name"
   echo "  --ldflags                   print flags passed to linker"
   echo "  --ldflags-before-libs       print flags passed to linker before linked libraries"
   echo "  --libs                      print linked libraries"
@@ -19,7 +21,9 @@ fi
 
 while [ $# -gt 0 ]; do
   case $1 in
+    --cc) echo MRUBY_CC;;
     --cflags) echo MRUBY_CFLAGS;;
+    --ld) echo MRUBY_LD;;
     --ldflags) echo MRUBY_LDFLAGS;;
     --ldflags-before-libs) echo MRUBY_LDFLAGS_BEFORE_LIBS;;
     --libs) echo MRUBY_LIBS;;

tasks/libmruby.rake

@@ -16,6 +16,9 @@ MRuby.each_target do
     open(t.name, 'w') do |f|
       f.puts "MRUBY_CFLAGS = #{cc.all_flags}"
 
+      f.puts "MRUBY_CC = #{cc.command}"
+      f.puts "MRUBY_LD = #{linker.command}"
+
       libgems = gems.reject{|g| g.bin?}
       gem_flags = libgems.map {|g| g.linker.flags }
       gem_library_paths = libgems.map {|g| g.linker.library_paths }