maint: update copyright

[gnulib.git] / m4 / atan2f.m4

diff --git a/m4/atan2f.m4 b/m4/atan2f.m4
index 34aeb59..311f94f 100644 (file)
--- a/m4/atan2f.m4
+++ b/m4/atan2f.m4
@@ -1,5 +1,5 @@
-# atan2f.m4 serial 1
-dnl Copyright (C) 2011 Free Software Foundation, Inc.
+# atan2f.m4 serial 2
+dnl Copyright (C) 2011-2014 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.
@@ -9,6 +9,9 @@ AC_DEFUN([gl_FUNC_ATAN2F],
   AC_REQUIRE([gl_MATH_H_DEFAULTS])
   AC_REQUIRE([gl_FUNC_ATAN2])
 
+  dnl Persuade glibc <math.h> to declare atan2f().
+  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+
   dnl Test whether atan2f() exists. Assume that atan2f(), if it exists, is
   dnl defined in the same library as atan2().
   save_LIBS="$LIBS"