release

[Matthew Fluet]

> > to mlton-basis.h.  That took care of everything except for int-overflow, which
> > is probably failing due to a problem unrelated to reals, but that hasn't been
> > noticed in a while.
> 
> Oops.  I forgot that the native backend still has overflow checking off by
> default.  All tests have now passed, so it was only the header file problem.

The native backend has overflow checking off by default?  (My reading of
control.sml and main.sml suggest that it is on by default.)