install-reloc: Support multi-binary installation.

[gnulib.git] / m4 / cbrt.m4

diff --git a/m4/cbrt.m4 b/m4/cbrt.m4
index 065f328..a6306c7 100644 (file)
--- a/m4/cbrt.m4
+++ b/m4/cbrt.m4
@@ -1,5 +1,5 @@
-# cbrt.m4 serial 1
-dnl Copyright (C) 2012 Free Software Foundation, Inc.
+# cbrt.m4 serial 2
+dnl Copyright (C) 2012-2013 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.
@@ -8,6 +8,9 @@ AC_DEFUN([gl_FUNC_CBRT],
 [
   AC_REQUIRE([gl_MATH_H_DEFAULTS])
 
+  dnl Persuade glibc <math.h> to declare cbrt().
+  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+
   dnl Determine CBRT_LIBM.
   gl_COMMON_DOUBLE_MATHFUNC([cbrt])