[m-rev.] for review: Enable munmap support in Boehm GC by default.

[Peter Wang]

On Wed, 22 Jul 2020 22:18:12 +1000 Peter Wang <novalazy at gmail.com> wrote:
> On Wed, 22 Jul 2020 21:54:49 +1000 Julien Fischer <jfischer at opturion.com> wrote:
> > 
> > >
> > > Some testing on my machine suggests that we can try enabling munmap
> > > support by default:

Unfortunately, I've found that by aggressively calling
GC_gcollect_and_unmap() I can sometimes hit an abort:

    mmap(PROT_NONE) failed

I'm going to revert this change until I can figure it out.

Peter