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+/* libc-internal interface for thread-specific data.  Stub or TLS version.
+   Copyright (C) 1998-2015 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/>.  */
+
+#ifndef _GENERIC_LIBC_TSD_H
+#define _GENERIC_LIBC_TSD_H 1
+
+/* This file defines the following macros for accessing a small fixed
+   set of thread-specific `void *' data used only internally by libc.
+
+   __libc_tsd_define(CLASS, TYPE, KEY)	-- Define or declare a datum with TYPE
+					   for KEY.  CLASS can be `static' for
+					   keys used in only one source file,
+					   empty for global definitions, or
+					   `extern' for global declarations.
+   __libc_tsd_address(TYPE, KEY)	-- Return the `TYPE *' pointing to
+					   the current thread's datum for KEY.
+   __libc_tsd_get(TYPE, KEY)		-- Return the `TYPE' datum for KEY.
+   __libc_tsd_set(TYPE, KEY, VALUE)	-- Set the datum for KEY to VALUE.
+
+   The set of available KEY's will usually be provided as an enum,
+   and contains (at least):
+		_LIBC_TSD_KEY_MALLOC
+		_LIBC_TSD_KEY_DL_ERROR
+		_LIBC_TSD_KEY_RPC_VARS
+   All uses must be the literal _LIBC_TSD_* name in the __libc_tsd_* macros.
+   Some implementations may not provide any enum at all and instead
+   using string pasting in the macros.  */
+
+#include <tls.h>
+
+/* When full support for __thread variables is available, this interface is
+   just a trivial wrapper for it.  Without TLS, this is the generic/stub
+   implementation for wholly single-threaded systems.
+
+   We don't define an enum for the possible key values, because the KEYs
+   translate directly into variables by macro magic.  */
+
+#define __libc_tsd_define(CLASS, TYPE, KEY)	\
+  CLASS __thread TYPE __libc_tsd_##KEY attribute_tls_model_ie;
+
+#define __libc_tsd_address(TYPE, KEY)		(&__libc_tsd_##KEY)
+#define __libc_tsd_get(TYPE, KEY)		(__libc_tsd_##KEY)
+#define __libc_tsd_set(TYPE, KEY, VALUE)	(__libc_tsd_##KEY = (VALUE))
+
+#endif	/* libc-tsd.h */