SSA

[Matthew Fluet]

> > > I'm currently trying to track down a bug in prodcons.sml.  Very strange;
> > > only shows up when running the regressions script and seems to be related
> > > to the new removeUnused pass for ssa.
> > 
> > Make sure it's not the same limit check bug :-).  Try running with big
> > heaps.
> 
> Well, some GC bug is contributing to prodcons.sml:

Similar problem on mutex.sml:

./regression: line 110: 20442 Aborted                 $f >$tmp 2>&1
13,21c13
< exiting
< exiting
< exiting
< exiting
< exiting
< exiting
< exiting
< exiting
< exiting
---
> gc.c 586: assert(0 == s->fromSize or (s->frontier <= s->limit + LIMIT_SLOP and s->limit == s->base + s->fromSize - LIMIT_SLOP)) failed.

Which also appears using the latest release with -g.

Since both of these asserts also occur with the release, I'm willing to
claim that they are limit check bugs.  If this is reasonable, then I'll
check in my latest changes, since the regression;self-compile;regression
only had the errors described above.