Some libgcc headers are missing the runtime exception

[David Edelsohn]

On Fri, Jul 9, 2021 at 1:31 PM Richard Sandiford
<richard.sandiford@arm.com> wrote:
>
> David Edelsohn <dje.gcc@gmail.com> writes:
> > On Fri, Jul 9, 2021 at 12:53 PM Richard Sandiford via Gcc
> > <gcc@gcc.gnu.org> wrote:
> >>
> >> Hi,
> >>
> >> It was pointed out to me off-list that config/aarch64/value-unwind.h
> >> is missing the runtime exception.  It looks like a few other files
> >> are too; a fuller list is:
> >>
> >> libgcc/config/aarch64/value-unwind.h
> >> libgcc/config/frv/frv-abi.h
> >> libgcc/config/i386/value-unwind.h
> >> libgcc/config/pa/pa64-hpux-lib.h
> >>
> >> Certainly for the aarch64 file this was simply a mistake;
> >> it seems to have been copied from the i386 version, both of which
> >> reference the runtime exception but don't actually include it.
> >>
> >> What's the procedure for fixing this?  Can we treat it as a textual
> >> error or do the files need to be formally relicensed?
> >
> > I'm unsure what you mean by "formally relicensed".
>
> It seemed like there were two possibilities: the licence of the files
> is actually GPL + exception despite what the text says (the textual
> error case), or the licence of the files is plain GPL because the text
> has said so since the introduction of the files.  In the latter case
> I'd have imagined that someone would need to relicense the code so
> that it is GPL + exception.
>
> > It generally is considered a textual omission.  The runtime library
> > components of GCC are intended to be licensed under the runtime
> > exception, which was granted and approved at the time of introduction.
>
> OK, thanks.  So would a patch to fix at least the i386 and aarch64 header
> files be acceptable?  (I'm happy to fix the other two as well if that's
> definitely the right thing to do.  It's just that there's more history
> involved there…)

Please correct the text in the files. The files in libgcc used in the
GCC runtime are intended to be licensed with the runtime exception and
GCC previously was granted approval for that licensing and purpose.

As you are asking the question, I sincerely doubt that ARM and Cavium
intended to apply a license without the exception to those files.  And
similarly for Intel and FRV.

The runtime exception explicitly was intended for this purpose and
usage at the time that GCC received approval to apply the exception.

Thanks, David