Re: igc, macOS avoiding signals

[Pip Cet]

"Helmut Eller" <eller.helmut@gmail.com> writes:
>> I find that difficult to understand. But it may be just a
>> statistical phenomenon. Maybe filling up an APs memory is so fast so
>> that the probability of a signal hitting while owning the mutex is close
>> to zero, or something.
>
> Very few of Emacs' signal handlers actually touch a barrier.  I've also

Indeed.  These crashes are rare in typical usage, which doesn't mean we
should delay fixing them until Emacs is "unstable enough".  It already
is, IMHO, because we take that approach too frequently.

> not seen any reproducable receipes for the "signal issues" that the igc
> branch supposedly has.

Removing the SIGPROF protection code should allow Ihor's recipe to crash
again.  And, anyway, there's no reason for the "supposedly": we know MPS
can't possibly deal with the situation because we've seen the code, so
we should fix it rather than ignoring it because it's rare in typical
usage.

If there's any evidence this cannot happen, I haven't seen it.

GC code in general contains many rarely-exercised code paths.  This is
no exception.

Pip