New module 'fabsl'.

* lib/math.in.h (fabsl): New declaration.
* lib/fabsl.c: New file.
* m4/fabsl.m4: New file.
* m4/math_h.m4 (gl_MATH_H): Test whether fabsl is declared.
(gl_MATH_H_DEFAULTS): Initialize GNULIB_FABSL, HAVE_FABSL,
REPLACE_FABSL.
* modules/math (Makefile.am): Substitute GNULIB_FABSL, HAVE_FABSL,
REPLACE_FABSL.
* modules/fabsl: New file.
* doc/posix-functions/fabsl.texi: Mention the new module.

1 files changed, 41 insertions, 0 deletions

diff --git a/lib/fabsl.c b/lib/fabsl.c
new file mode 100644
index 0000000000..ca89631faf
--- /dev/null
+++ b/lib/fabsl.c
@@ -0,0 +1,41 @@
+/* Absolute value.
+   Copyright (C) 2012 Free Software Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+/* Specification.  */
+#include <math.h>
+
+/* fabsl (x) can be defined as copysignl (x, 1.0L).
+   Or, more directly, as (signbit (x) ? - x : x).  */
+
+#if HAVE_SAME_LONG_DOUBLE_AS_DOUBLE
+
+long double
+fabsl (long double x)
+{
+  return fabs (x);
+}
+
+#else
+
+long double
+fabsl (long double x)
+{
+  return (signbit (x) ? - x : x);
+}
+
+#endif