[Bug tree-optimization/56034] [4.8 Regression] ICE: verify_gimple failed (invalid PHI argument) with -ftree-loop-distribution

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56034



--- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> 2013-01-25 
18:16:08 UTC ---

(In reply to comment #4)

> So, we replace

> # a.0_26 = PHI <a.0_10(5)>

> with

> # a.0_26 = PHI <.MEM_10(5)>

> This happens when we call rewrite_into_loop_closed_ssa in case we're actually

> performing some loop distribution transformation.  Then we call update_ssa and

> here with

>       FOR_EACH_VEC_ELT (symbols_to_rename, i, sym) 

>         insert_updated_phi_nodes_for (sym, dfs, blocks_to_update,

>                                       update_flags);

> change the PHI argument.



Note that this only can happen if a.0_10 was released but still used before.



I'm still going to look into this after I return on monday.