Re: MPS: assertion failed: header_type (h) != IGC_OBJ_FWD

[Pip Cet <pipcet@protonmail.com>]

On Friday, July 19th, 2024 at 04:38, Gerd Möllmann <gerd.moellmann@gmail.com> wrote:
> Gerd Möllmann gerd.moellmann@gmail.com writes:
> 
> > Andrea Corallo acorallo@gnu.org writes:
> > 
> > > > Let's see how long igc survives this time :-).
> > > 
> > > Hi Gerd,
> > > 
> > > if you want to use '__builtin_unwind_init' be aware that this GCC bug
> > > I've found sometime ago [1] might make the builtin ineffective. It
> > > might not effect your generated code but in case you need you can see
> > > how we work it around in 'flush_stack_call_func'.
> > > 
> > > Regards
> > 
> > Thanks, that could become important at some point on platforms other
> > than macOS. AFAIK, one cannot build Emacs with GCC on newer versions of
> > macOS because the SDK is incompatible with GCC, so GCC is out of the
> > picture.
> > 
> > I haven't heard yet of anyone else having problems of the sort I have
> > here on macOS on other platforms. But maybe that comes up later.
> 
> 
> It didn't help, and no more ideas at the moment :-(.

Can you try compiling with -fno-omit-frame-pointer? I just spent entirely too much time tracing down a bug in my build to a missing option (of the same name) to x86_64 gcc. The frame pointer is stored in a mangled format by setjmp() on both darwin and glibc systems, and that caused weird problems (and since gcc generates different code with and without "-g", I had to do that without proper debugger support...)

Anyway, I think both architectures "allow" using the frame pointer register, so we're probably going to have to enforce that option, which will limit us to clang and gcc compilers unless someone figures out the configure magic...

Pip