Libgcc symbols

[Richard Kenner]

    > It was used in builtin setjmp support to get GP properly restored on
    > machines where it was needed.  I don't see it in the current
    > sources, so I'm curious how this was done instead.

    builtin_setjmp_receiver

Yes, I know that's where this sort of thing is supposed to be done, but
as far as I know, there's no way in the MIPS assembler (for O32 calling
convention) to actually *do* the GP restore.