Add tests for sign of NaN returned by strtod (bug 23007).

This patch adds tests for bug 23007, strtod ignoring any sign in the
input string in the case of a NaN result.

Tested for x86_64.

	[BZ #23007]
	* stdlib/tst-strtod-nan-sign-main.c: New file.
	* stdlib/tst-strtod-nan-sign.c: Likewise.
	* wcsmbs/tst-wcstod-nan-sign.c: Likewise.
	* stdlib/Makefile (tests): Add tst-strtod-nan-sign.
	($(objpfx)tst-strtod-nan-sign): Depend on $(libm).
	* wcsmbs/Makefile (tests) Add tst-wcstod-nan-sign.
	($(objpfx)tst-wcstod-nan-sign): Depend on $(libm).

1 files changed, 23 insertions, 0 deletions

diff --git a/stdlib/tst-strtod-nan-sign.c b/stdlib/tst-strtod-nan-sign.c
new file mode 100644
index 0000000000..0b99932417
--- /dev/null
+++ b/stdlib/tst-strtod-nan-sign.c
@@ -0,0 +1,23 @@
+/* Test strtod functions handle signs of NaNs (bug 23007).
+   Narrow string version.
+   Copyright (C) 2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#define FNPFX strto
+#define L_(C) C
+
+#include <tst-strtod-nan-sign-main.c>