[Bug tree-optimization/29516] gfortran miscompiled

[rakdver at gcc dot gnu dot org]

------- Comment #19 from rakdver at gcc dot gnu dot org  2007-01-09 20:45 -------
(In reply to comment #14)
> (which gcc version are the dumps created with?)
> 
> First IVOPTs should not create pointer multiplication.  Really.  Second, the
> problem is probably in tree-vrp.c:adjust_range_with_scev () or SCEV itself -
> I guess SCEV might be confused by this multiplication as well.

The problem is really only ivopts, creating pointer multiplication.  I have
seen this bug before, after some changes to ivopts, but it is quite hard to
reproduce -- one needs to force ivopts to generate pointer offset multiplied by
a negative number and ivopts do not do that very often (the circumstances have
to be really strange to make this appear useful).

I will prepare a patch.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29516