configure.in: workaround of mingw-w64

* configure.in (NET_LUID): include also ifdef.h as a workaround of
  a bug in mingw-w64 header.  [ruby-core:67103] [Bug #10640]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@48988 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,8 @@
+Thu Dec 25 13:59:17 2014  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* configure.in (NET_LUID): include also ifdef.h as a workaround of
+	  a bug in mingw-w64 header.  [ruby-core:67103] [Bug #10640]
+
 Thu Dec 25 12:47:44 2014  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* parse.y (gettable_gen): warn possible reference to a local

configure.in

@@ -1103,6 +1103,7 @@ main()
 		{ test "$target_cpu" = x64 && ac_cv_func___builtin_setjmp=no; }
 		AC_CHECK_TYPE([NET_LUID], [], [],
 			      [@%:@include <windows.h>
+			      @%:@include <ifdef.h>
 			      @%:@include <iphlpapi.h>])
 		if test x"$ac_cv_type_NET_LUID" = xyes; then
 		    AC_DEFINE(HAVE_TYPE_NET_LUID, 1)