--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2010-12-21  Bruno Haible  <bruno@clisp.org>
+
+	New module 'truncl-ieee'.
+	* modules/truncl-ieee: New file.
+	* modules/truncl-ieee-tests: New file.
+	* tests/test-truncl-ieee.c: New file, based on tests/test-truncl.c.
+	* tests/test-truncl.c (main): Remove signbit tests.
+	* modules/truncl-tests (Depends-on): Remove signbit.
+	* doc/posix-functions/truncl.texi: Mention the new module.
+
 2010-12-21  Bruno Haible  <bruno@clisp.org>
 
 	New module 'ceill-ieee'.

--- a/doc/posix-functions/truncl.texi
+++ b/doc/posix-functions/truncl.texi
@@ -4,7 +4,7 @@
 
 POSIX specification:@* @url{http://www.opengroup.org/onlinepubs/9699919799/functions/truncl.html}
 
-Gnulib module: truncl
+Gnulib module: truncl or truncl-ieee
 
 Portability problems fixed by Gnulib:
 @itemize

new file mode 100644
--- /dev/null
+++ b/modules/truncl-ieee
@@ -0,0 +1,23 @@
+Description:
+truncl() function according to ISO C 99 with IEC 60559.
+
+Files:
+
+Depends-on:
+truncl
+
+configure.ac:
+
+Makefile.am:
+
+Include:
+<math.h>
+
+Link:
+$(TRUNCL_LIBM)
+
+License:
+LGPL
+
+Maintainer:
+Bruno Haible

new file mode 100644
--- /dev/null
+++ b/modules/truncl-ieee-tests
@@ -0,0 +1,16 @@
+Files:
+tests/test-truncl-ieee.c
+tests/minus-zero.h
+tests/macros.h
+
+Depends-on:
+fpucw
+float
+signbit
+
+configure.ac:
+
+Makefile.am:
+TESTS += test-truncl-ieee
+check_PROGRAMS += test-truncl-ieee
+test_truncl_ieee_LDADD = $(LDADD) @TRUNCL_LIBM@

--- a/modules/truncl-tests
+++ b/modules/truncl-tests
@@ -9,7 +9,6 @@
 fpucw
 isnanl-nolibm
 float
-signbit
 
 configure.ac:
 

new file mode 100644
--- /dev/null
+++ b/tests/test-truncl-ieee.c
@@ -0,0 +1,37 @@
+/* Test of rounding towards zero.
+   Copyright (C) 2010 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>
+
+#include <math.h>
+
+#include "fpucw.h"
+#include "minus-zero.h"
+#include "macros.h"
+
+int
+main ()
+{
+  DECL_LONG_DOUBLE_ROUNDING
+
+  BEGIN_LONG_DOUBLE_ROUNDING ();
+
+  /* Zero.  */
+  ASSERT (!signbit (truncl (0.0L)));
+  ASSERT (!!signbit (truncl (minus_zerol)) == !!signbit (minus_zerol));
+
+  return 0;
+}

--- a/tests/test-truncl.c
+++ b/tests/test-truncl.c
@@ -40,9 +40,7 @@
 
   /* Zero.  */
   ASSERT (truncl (0.0L) == 0.0L);
-  ASSERT (!signbit (truncl (0.0L)));
   ASSERT (truncl (minus_zerol) == 0.0L);
-  ASSERT (!!signbit (minus_zerol) == !!signbit (truncl (minus_zerol)));
   /* Positive numbers.  */
   ASSERT (truncl (0.3L) == 0.0L);
   ASSERT (truncl (0.7L) == 0.0L);