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From: "michael.collison at linaro dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug debug/61033] [4.8/4.9 Regression] Infinite loop in variable tracking
Date: Mon, 04 Aug 2014 18:55:00 -0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61033

--- Comment #7 from Michael Collison <michael.collison at linaro dot org> ---
Charlie,

I still feel that the var tracking pass should be able to protect itself 
from an infinite loop.

On 8/4/2014 11:43 AM, cbaylis at gcc dot gnu.org wrote:
> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61033
>
> --- Comment #6 from cbaylis at gcc dot gnu.org ---
>
> git bisect points to r211625 as the revision which fixes/hides this bug on
> trunk.
>
> 2014-06-13  Richard Biener  <rguenther@suse.de>
>
>          * tree-ssa-pre.c (eliminate_dom_walker::before_dom_children):
>          Rewrite to propagate the VN result into all uses where
>          possible and to remove stmts becoming dead because of that.
>          (eliminate): Generalize stmt removal handling, remove in
>          reverse dominator order to support proper debug stmt
>          generation.  Update stmts before removing stmts.
>          * tree-ssa-propagate.c (propagate_tree_value): Remove
>          bogus assert.
>