[Bug middle-end/47566] ICE in vn_reference_lookup

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47566

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |rguenth at gcc dot gnu.org

--- Comment #4 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-02-01 12:12:13 UTC ---
(In reply to comment #3)
> (In reply to comment #2)
> > I think we need source code (LTO bytecode isn't really portable).
> 
> oops... that's building CP2K. Let me see if I can reproduce this with this
> night's tarball.
> 
> > 
> > (gdb) call debug_tree (vuse)
> > 
> > at that point?
> 
> (gdb)  call debug_tree (vuse)
>  <var_decl 0x7ffff532eb40 .MEM
>     type <void_type 0x7ffff7e84d20 void VOID
>         align 8 symtab 0 alias set -1 structural equality
>         pointer_to_this <pointer_type 0x7ffff7e84dc8>>
>     used static external VOID file <built-in> line 0 col 0
>     align 8>

That's indeed invalid - it should be an SSA name.  This means some
earlier pass messed up (or PRE itself).  The bug shouldn't depend
on LTO (apart from maybe requiring some cross-module inlining to trigger).