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).

3 files changed, 75 insertions, 1 deletions

diff --git a/stdlib/Makefile b/stdlib/Makefile
index bf1fbd4a3a..808a8ceab7 100644
--- a/stdlib/Makefile
+++ b/stdlib/Makefile
@@ -84,7 +84,7 @@ tests		:= tst-strtol tst-strtod testmb testrand testsort testdiv   \
 		   tst-cxa_atexit tst-on_exit test-atexit-race 		    \
 		   test-at_quick_exit-race test-cxa_atexit-race             \
 		   test-on_exit-race test-dlclose-exit-race 		    \
-		   tst-makecontext-align test-bz22786
+		   tst-makecontext-align test-bz22786 tst-strtod-nan-sign
 
 tests-internal	:= tst-strtod1i tst-strtod3 tst-strtod4 tst-strtod5i \
 		   tst-tls-atexit tst-tls-atexit-nodelete
@@ -221,6 +221,7 @@ $(objpfx)tst-tininess: $(libm)
 $(objpfx)tst-strtod-underflow: $(libm)
 $(objpfx)tst-strtod6: $(libm)
 $(objpfx)tst-strtod-nan-locale: $(libm)
+$(objpfx)tst-strtod-nan-sign: $(libm)
 
 tst-tls-atexit-lib.so-no-z-defs = yes
 test-dlclose-exit-race-helper.so-no-z-defs = yes
diff --git a/stdlib/tst-strtod-nan-sign-main.c b/stdlib/tst-strtod-nan-sign-main.c
new file mode 100644
index 0000000000..b168c64208
--- /dev/null
+++ b/stdlib/tst-strtod-nan-sign-main.c
@@ -0,0 +1,50 @@
+/* Test strtod functions handle signs of NaNs (bug 23007).
+   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/>.  */
+
+#include <math.h>
+#include <stdlib.h>
+#include <wchar.h>
+
+#include <stdlib/tst-strtod.h>
+#include <support/check.h>
+
+#define CONCAT_(X, Y) X ## Y
+#define CONCAT(X, Y) CONCAT_ (X, Y)
+#define FNX(FN) CONCAT (FNPFX, FN)
+
+#define TEST_STRTOD(FSUF, FTYPE, FTOSTR, LSUF, CSUF)	\
+static int						\
+test_strto ## FSUF (void)				\
+{							\
+  FTYPE val_pos = FNX (FSUF) (L_("nan"), NULL);		\
+  FTYPE copy_pos = copysign ## CSUF (1, val_pos);	\
+  TEST_VERIFY (isnan (val_pos) && copy_pos == 1);	\
+  FTYPE val_neg = FNX (FSUF) (L_("-nan"), NULL);	\
+  FTYPE copy_neg = copysign ## CSUF (1, val_neg);	\
+  TEST_VERIFY (isnan (val_neg) && copy_neg == -1);	\
+  return 0;						\
+}
+GEN_TEST_STRTOD_FOREACH (TEST_STRTOD)
+
+static int
+do_test (void)
+{
+  return STRTOD_TEST_FOREACH (test_strto);
+}
+
+#include <support/test-driver.c>
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>