wcpcpy, wcpncpy: Ensure declaration on glibc >= 2.13 systems.

[gnulib.git] / m4 / wcpncpy.m4

diff --git a/m4/wcpncpy.m4 b/m4/wcpncpy.m4
index 939e880..a4d73e2 100644 (file)
--- a/m4/wcpncpy.m4
+++ b/m4/wcpncpy.m4
@@ -1,4 +1,4 @@
-# wcpncpy.m4 serial 1
+# wcpncpy.m4 serial 2
 dnl Copyright (C) 2011 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -7,6 +7,10 @@ dnl with or without modifications, as long as this notice is preserved.
 AC_DEFUN([gl_FUNC_WCPNCPY],
 [
   AC_REQUIRE([gl_WCHAR_H_DEFAULTS])
+
+  dnl Persuade glibc <wchar.h> to declare wcpncpy().
+  AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
+
   AC_CHECK_FUNCS_ONCE([wcpncpy])
   if test $ac_cv_func_wcpncpy = no; then
     HAVE_WCPNCPY=0