* sysdeps/mach/hurd/i386/trampoline.c: Add a link to
SS->active_resources, so that _hurdsig_longjmp_from_handler will
be called when a longjmp unwinds the signal frame.
* sysdeps/mach/hurd/i386/sigreturn.c: Remove the link on the
SS->active_resources chain added by _hurd_setup_sighandler.
* hurd/sigunwind.c: New file.
* hurd/Makefile (sig): Add sigunwind.
* Makerules (lib%.so: lib%_pic.a): Remove dir name from $*.
* MakeTAGS (tags-sources): Include $(all-dist).
[subdir] (all-dist): Define to $(distribute).