[tree-ssa] Problem with constant folding

[law@redhat.com]

In message <20031209083351.GA14478@atrey.karlin.mff.cuni.cz>, Zdenek Dvorak wri
tes:
 >Hello,
 >
 >[snip] (http://gcc.gnu.org/ml/gcc-patches/2003-12/msg00786.html)
 >
 >> The patch below fixes the problem by preventing the overflowed constants
 >> from being propagated.  It is probably way too conservative, but I was
 >> not able to determine the place where to fix the problem in other way.
 >
 >... and unfortunately it is also wrong, since it fails to bootstrap. Does
 >someone has an idea what is the right way to fix this?
Your approach seems pretty reasonable.  And it seems extremely odd that
it wouldn't bootstrap since it ought to just force such constants into
new variables and prevent them from being propagated by the optimizers.

I'd suggest investigating why the patch didn't bootstrap.


jeff