Import new gnulib.

m4/mbsinit.m4

@@ -1,5 +1,5 @@
-# mbsinit.m4 serial 4
-dnl Copyright (C) 2008, 2010 Free Software Foundation, Inc.
+# mbsinit.m4 serial 8
+dnl Copyright (C) 2008, 2010-2013 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
@@ -7,6 +7,7 @@ dnl with or without modifications, as long as this notice is preserved.
 AC_DEFUN([gl_FUNC_MBSINIT],
 [
   AC_REQUIRE([gl_WCHAR_H_DEFAULTS])
+  AC_REQUIRE([AC_CANONICAL_HOST])
 
   AC_REQUIRE([AC_TYPE_MBSTATE_T])
   gl_MBSTATE_T_BROKEN
@@ -14,16 +15,34 @@ AC_DEFUN([gl_FUNC_MBSINIT],
   AC_CHECK_FUNCS_ONCE([mbsinit])
   if test $ac_cv_func_mbsinit = no; then
     HAVE_MBSINIT=0
+    AC_CHECK_DECLS([mbsinit],,, [[
+/* Tru64 with Desktop Toolkit C has a bug: <stdio.h> must be included before
+   <wchar.h>.
+   BSD/OS 4.0.1 has a bug: <stddef.h>, <stdio.h> and <time.h> must be
+   included before <wchar.h>.  */
+#include <stddef.h>
+#include <stdio.h>
+#include <time.h>
+#include <wchar.h>
+]])
+    if test $ac_cv_have_decl_mbsinit = yes; then
+      dnl On Minix 3.1.8, the system's <wchar.h> declares mbsinit() although
+      dnl it does not have the function. Avoid a collision with gnulib's
+      dnl replacement.
+      REPLACE_MBSINIT=1
+    fi
   else
     if test $REPLACE_MBSTATE_T = 1; then
       REPLACE_MBSINIT=1
+    else
+      dnl On mingw, mbsinit() always returns 1, which is inappropriate for
+      dnl states produced by mbrtowc() for an incomplete multibyte character
+      dnl in multibyte locales.
+      case "$host_os" in
+        mingw*) REPLACE_MBSINIT=1 ;;
+      esac
     fi
   fi
-  if test $HAVE_MBSINIT = 0 || test $REPLACE_MBSINIT = 1; then
-    gl_REPLACE_WCHAR_H
-    AC_LIBOBJ([mbsinit])
-    gl_PREREQ_MBSINIT
-  fi
 ])
 
 # Prerequisites of lib/mbsinit.c.