christos@NetBSD.org said:
> Modified Files:
> 	src/include: signal.h
> Log Message: Provide forward struct declarations for struct
> sigcontext*;

As I see it, this should be done more radically.
sigreturn() isn't supported for compilation from source
anymore - it is just present for binary comaptibility in
conjunction with a COMPAT_16 kernel. So neither sigreturn()
nor sigcontext need to be exported to user programs.
It might remain within __LIBC12_SOURCE__, but even that
is unnecessary because there are only assembler stubs
which implement sigreturn().
(Actually, I missed that __HAVE_SIGINFO when I did some
cleanup last year.)

> this will allow us to get rid of them in the machine/
> signal.h files. 

What's the plan? I agree that the sigcontext defs are
unnecessary outside of compat code.

best regards
Matthias