Currently Parrot installs just one handler (SIGHUP) for testing only.
See src/events.c. So old issues WRT ponie regression tests should be
solved.

Shouldn't be too hard, yes.

A lot of interface functions are still missing.

The stack top has to be beyond any variables Parrot might see. When
during DOD the stack (and the CPU registers) are traced all possible
pointers to PMCs and Buffers must be covered by the range of the stack
top and the current stack pointer.

This doesn't work:

  {
    PMC *x = pmc_new(..);
    {
       some_parrot_func();
    }
  }

C<x> would be outside of the visible range of stack items. The braces do
of course indicate stack frames.

No. There is a lot:

void Parrot_runops_fromc(Parrot_Interp, PMC *sub);
void Parrot_runops_fromc_save(Parrot_Interp, PMC *sub);
void* Parrot_runops_fromc_args(Parrot_Interp, PMC *sub, const char *sig, ...);
void* Parrot_runops_fromc_args_save(Parrot_Interp, PMC *, const char *, ...);
INTVAL Parrot_runops_fromc_args_save_reti(Parrot_Interp, PMC *,
        const char *, ...);
FLOATVAL Parrot_runops_fromc_args_save_retf(Parrot_Interp, PMC *,
        const char *, ...);

plus a bunch more to run method functions.

see perldoc -F src/interpreter.c

NCI calls C functions from byte code. Calling PASM/PIR from C is done
with above functions. And there is PASM->C->PASM via callback functions.

Yep. A lot of. What's perl5 doing against those?

No problem.

leo