Fix strtod ("NAN(I)") in Turkish locales (bug 19266).

The implementations of strtod and related functions use
locale-specific conversions to lower case when parsing the contents of
a string NAN(n-char-sequence_opt).  This has the consequence that
NAN(I) is not treated as being of that form (only the initial NAN part
is accepted).  The syntax of n-char-sequence directly maps to the
ASCII letters, digits and underscore as in identifiers, so it is
unambiguous that all ASCII letters must be accepted in all locales.

This patch, relative to a tree with
<https://sourceware.org/ml/libc-alpha/2015-11/msg00258.html> (pending
review) applied and depending on that patch, fixes this problem by
checking directly for ASCII letters.  This will have the side effect
of no longer accepting 'İ' (dotted 'I') inside NAN() in Turkish
locales, which seems appropriate (that letter wouldn't have been
interpreted as having any meaning in the NaN payload anyway, as not
acceptable to strtoull).

Tested for x86_64 and x86.

	[BZ #19266]
	* stdlib/strtod_l.c (____STRTOF_INTERNAL): Check directly for
	upper case and lower case letters inside NAN(), not using TOLOWER.
	* stdlib/tst-strtod-nan-locale-main.c: New file.
	* stdlib/tst-strtod-nan-locale.c: Likewise.
	* stdlib/Makefile (tests): Add tst-strtod-nan-locale.
	[$(run-built-tests) = yes] ($(objpfx)tst-strtod-nan-locale.out):
	Depend on $(gen-locales).
	($(objpfx)tst-strtod-nan-locale): Depend on $(libm).
	* wcsmbs/tst-wcstod-nan-locale.c: New file.
	* wcsmbs/Makefile (tests): Add tst-wcstod-nan-locale.
	[$(run-built-tests) = yes] ($(objpfx)tst-wcstod-nan-locale.out):
	Depend on $(gen-locales).
	($(objpfx)tst-wcstod-nan-locale): Depend on $(libm).

1 files changed, 25 insertions, 0 deletions

diff --git a/stdlib/tst-strtod-nan-locale.c b/stdlib/tst-strtod-nan-locale.c
new file mode 100644
index 0000000000..b65f7c0904
--- /dev/null
+++ b/stdlib/tst-strtod-nan-locale.c
@@ -0,0 +1,25 @@
+/* Test strtod functions work with all ASCII letters in NAN(...) in
+   Turkish locales (bug 19266).  Narrow string version.
+   Copyright (C) 2015 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 CHAR char
+#define SFMT "\"%s\""
+#define FNPFX strto
+#define L_(C) C
+
+#include <tst-strtod-nan-locale-main.c>