additional license file in libffi source distribution?

[Anthony Green <green@moxielogic.com>]

Several people have pointed out that msvcc.sh and
testsuite/libffi.bhaible are both covered by licensing terms that are
different from the libffi license, and that we need to (a) remove them, or
(b) include the license text.  I'd rather include the license text (GPLv2),
as they are convenient to bundle and maintain along with the libffi source
code.   To that end, I just added a LICENSE-BUILDTOOLS file with the GPLv2
license, and a short preamble included below.  IANAL, but my intent is to
make sure that nobody can credibly claim that libffi should be covered by
the GPL.  Any comments or suggestions on improving this?:

---- cut here ---------------------------------------
The libffi source distribution contains certain code that is not part
of libffi, and is only used as tooling to assist with the building and
testing of libffi.  This includes the msvcc.sh script used to wrap the
Microsoft compiler with GNU compatible command-line options, and the
libffi test code distributed in the testsuite/libffi.bhaible
directory.  This code is distributed with libffi for the purpose of
convenience only, and libffi is in no way derived from this code.

msvcc.sh an testsuite/libffi.bhaible are both distributed under the
terms of the GNU GPL version 2, as below.

[text of GPLv2 redacted]
---- cut here ---------------------------------------

I wonder about this because some tools, like config.sub and ltmain.sh say
they are GPLv2 _except_ when bundled with other programs, in which case
they assume the other program's license.   Why do they need to do that?

Thanks,

AG