X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Ftanf.m4;h=8569080bea3cb3c2759ecd92f12a28859fd6efa7;hb=7ef6c64e210ac0979d7e8ac69bc5b5208c2405ab;hp=37f48743b809bd8cf3f9fd5d735eb463a7754cdb;hpb=3a018a7f9b0c254103a6c191b74a4b72e296af34;p=gnulib.git

diff --git a/m4/tanf.m4 b/m4/tanf.m4
index 37f48743b..8569080be 100644
--- a/m4/tanf.m4
+++ b/m4/tanf.m4
@@ -1,5 +1,5 @@
-# tanf.m4 serial 1
-dnl Copyright (C) 2011 Free Software Foundation, Inc.
+# tanf.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_TANF],
   AC_REQUIRE([gl_MATH_H_DEFAULTS])
   AC_REQUIRE([gl_FUNC_TAN])
 
+  dnl Persuade glibc <math.h> to declare tanf().
+  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+
   dnl Test whether tanf() exists. Assume that tanf(), if it exists, is
   dnl defined in the same library as tan().
   save_LIBS="$LIBS"