Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Fix several clang warnings in libstdc++, which were exposed by the
recent atf import. These changes are purely cosmetic, no functional
change.

MFC after: 1 week

Update libstdc++ with small updates from the latest rev. (135556)
from the gcc 4.2 branch.
The libraries in the gcc-4_2-branch remained under the LGPLv2.

The changes can be reproduced with the following command:

svn diff svn://gcc.gnu.org/svn/gcc/branches/gcc-4_2-branch/libstdc++-v3
-r 127959:135556

Reviewed by: mm
Approved by: jhb (mentor)
MFC after: 2 weeks

This commit was generated by cvs2svn to compensate for changes in r169691,
which included commits to RCS files with non-trunk default branches.

GCC 4.2.0 release C++ standard library and runtime support code.

Gcc 3.4.6 C++ support bits (as of 2006/08/25 #116475).

Gcc 3.4.4 C++ support bits.

Gcc 3.4.2 20040728 C++ support bits.

Gcc 3.3.1-pre 2003-07-11 C++ support bits.

Gcc 3.2.2-release C++ support bits.

Gcc 3.2.1 release virgin vendor import. (19-Nov-2002)

Gcc 3.2.1-prerelease libf2c bits from the FSF anoncvs repo gcc-3_2-branch on 1-Sep-2002 00:00:01 EDT.

Gcc 3.1.0 pre-release's C++ support bits from the FSF anoncvs repo
on 9-May-2002 15:57:15 EDT.