Merge GDB 7.5.1

gdb/gnulib/extra/arg-nonnull.h

-/* A C macro for declaring that specific arguments must not be NULL.
-   Copyright (C) 2009, 2010, 2011 Free Software Foundation, Inc.
-
-   This program is free software: you can redistribute it and/or modify it
-   under the terms of the GNU General Public License as published
-   by the Free Software Foundation; either version 3 of the License, or
-   (at your option) any later version.
-
-   This program 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 General Public License
-   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
-
-/* _GL_ARG_NONNULL((n,...,m)) tells the compiler and static analyzer tools
-   that the values passed as arguments n, ..., m must be non-NULL pointers.
-   n = 1 stands for the first argument, n = 2 for the second argument etc.  */
-#ifndef _GL_ARG_NONNULL
-# if (__GNUC__ == 3 && __GNUC_MINOR__ >= 3) || __GNUC__ > 3
-#  define _GL_ARG_NONNULL(params) __attribute__ ((__nonnull__ params))
-# else
-#  define _GL_ARG_NONNULL(params)
-# endif
-#endif