Re: 'stack overflow' message for Darwin; host hooks

[Zack Weinberg <zack at codesourcery dot com>]

Geoffrey Keating <gkeating@apple.com> writes:

> This patch does two thing: 
>
> 1. It establishes a system for host-specific callbacks.  The system is
>    way too elaborate for the trivial purpose in the patch, but I plan
>    do extend it later to add host-specific ways to detect that we
>    don't need to do a GC collection right now, and to perform
>    incremental GC.

Cute, but would you mind putting some thought into a way to avoid a
re-proliferation of x-fragments?  I went to considerable effort to get
within epsilon of being able to eliminate that facility entirely.

> 2. It fixes an annoying UI issue with GCC on Darwin.  Darwin has the
>    default soft stack limit set to 512k, which can be easily tripped
>    over; in fact, some tests in the GCC testsuite hit it.  Before,
>    when this happened GCC would print 'Internal error: bus error',
>    which is an incredibly unhelpful error message; now it prints
>    'Out of stack memory.' and a message saying how to change the
>    limit.

I thought we had code in toplev.c to call rlimit() to set the soft
stack limit as high as it could go, rather than bothering the user
about it.

zw