--- /dev/null
+/* MPFR internal header related to thread-local variables.
+
+Copyright 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
+Contributed by the Arenaire and Cacao projects, INRIA.
+
+This file is part of the GNU MPFR Library.
+
+The GNU MPFR 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 MPFR 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 MPFR Library; see the file COPYING.LIB. If not, write to
+the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
+MA 02110-1301, USA. */
+
+#ifndef __MPFR_THREAD_H__
+#define __MPFR_THREAD_H__
+
+/* Note: Let's define MPFR_THREAD_ATTR even after a #error to make the
+ error message more visible (e.g. gcc doesn't immediately stop after
+ the #error line and outputs many error messages if MPFR_THREAD_ATTR
+ is not defined). But some compilers will just output a message and
+ may build MPFR "successfully" (without thread support). */
+#ifndef MPFR_THREAD_ATTR
+# ifdef MPFR_USE_THREAD_SAFE
+# if defined(_MSC_VER)
+# if defined(_WINDLL)
+# error "Can't build MPFR DLL as thread safe."
+# define MPFR_THREAD_ATTR
+# else
+# define MPFR_THREAD_ATTR __declspec( thread )
+# endif
+# else
+# define MPFR_THREAD_ATTR __thread
+# endif
+# else
+# define MPFR_THREAD_ATTR
+# endif
+#endif
+
+#endif