* configure.in: add --with-ntver option to match win32/configure.bat

functionality. Set 0x0501 as default. [ruby-core:35010]
  [ruby-core:35035]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@34118 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,9 @@
+Sat Dec 24 23:25:15 2011  Luis Lavena  <luislavena@gmail.com>
+
+	* configure.in: add --with-ntver option to match win32/configure.bat
+	  functionality. Set 0x0501 as default. [ruby-core:35010]
+	  [ruby-core:35035]
+
 Sat Dec 24 12:38:53 2011  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* proc.c (proc_call): get rid of optimazation-out by clang.

configure.in

@@ -940,6 +940,14 @@ AC_ARG_ENABLE(win95,
 	AS_HELP_STRING([--enable-win95], [enable Windows 95 series support]),
   [AS_CASE(["$enableval"],[yes|no],[enable_win95=$enableval],[unset enable_win95])])
 
+AC_ARG_WITH(ntver,
+  AS_HELP_STRING([--with-ntver=0xXXXX], [target NT version (default to 0x0501)]),
+  [with_ntver="$withval"], [with_ntver="0x0501"])
+AS_CASE(["$target_os"],
+[mingw*], [
+  RUBY_APPEND_OPTION(CPPFLAGS, -D_WIN32_WINNT=$with_ntver)
+])
+
 AS_CASE(["$target_os"],
 [freebsd*], [
   AC_CACHE_CHECK([whether pthread should be enabled by default],