Hi,
    I want to back port a libiberty patch from gcc tree
so that gdb can build with clang. The patch is clean to
gdb tree except that the ChangeLog is different.
    I also attached patch with modification of the ChangeLog.

    Thanks

commit 19ecc7c1742ebd58f7b940da6cee3c6891020f1e
Author: ian <ian@138bc75d-0d04-0410-961f-82ee72b054a4>
Date:   Fri May 22 20:53:45 2015 +0000

    include/:
        * libiberty.h (asprintf): Don't declare if HAVE_DECL_ASPRINTF is
        not defined.
    libiberty/:
        * configure.ac: Add AC_GNU_SOURCE.
        * Makefile.in (COMPILE.c): Add -D_GNU_SOURCE.
        * configure, config.in: Rebuild.
        * floatformat.c (_GNU_SOURCE): Don't define if already defined.