[Bug tree-optimization/22277] [4.1 Regression] ACATS ICE cc40001 in first_vi_for_offset, at tree-ssa-structalias.c:2566

["dberlin at dberlin dot org" <gcc-bugzilla at gcc dot gnu dot org>]

------- Additional Comments From dberlin at gcc dot gnu dot org  2005-07-11 12:33 -------
Subject: Re:  [4.1 Regression] ACATS ICE
	cc40001 in first_vi_for_offset, at tree-ssa-structalias.c:2566

On Mon, 2005-07-11 at 08:48 +0000, reichelt at gcc dot gnu dot org
wrote:
> ------- Additional Comments From reichelt at gcc dot gnu dot org  2005-07-11 08:48 -------
> More compact C++ testcase:
> 
> ======================================
> struct A
> {
>   char c;
>   int i;
> };
> 
> A a;
> 
> struct B
> {
>   char c, d;
> };
> 
> union C
> {
>   A *p;
>   B *q;
> 
>   C() : p(&a) {}
>   char& foo() { return q->d; }
> };
> 
> void bar() { C().foo() = 0; }

Yes, that will work too.

Note the part that bugs me severely is that you are accessing padding in
A. :)  This is true in the original testcase as well
I'm not sure whether i should bother trying to do something sane in this
case.




-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22277