[Bug c/60101] [4.7/4.8/4.9 Regression] Long compile times when mixed complex floating point datatypes are used in lengthy expressions

["manu at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60101

--- Comment #8 from Manuel López-Ibáñez <manu at gcc dot gnu.org> ---
(In reply to Jakub Jelinek from comment #7)
> passes with this change and the testcase from this PR finishes in under a
> second.  Manuel, can you please try to explain what you were trying to
> achieve in the SAVE_EXPR case and whether the reversal of copy behavior in
> merge_tlist was on purpose?

I don't remember I implemented this part (the revision that you mention is not
adding the handling of SAVE_EXPR or the reversal of copy behavior). My patch
simply extended the definition of what is considered candidates for warning (by
looking at the operands of operators). I took a look at my patch, and I don't
fully understand how it triggers the bug that you mention. Perhaps there is
some duplication between the code path that I added (since it is meant to
recurse on operands) and some special-handling that was there for SAVE_EXPR and
COND_EXPR.
>From gcc-bugs-return-443277-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org Tue Feb 11 13:14:27 2014
Return-Path: <gcc-bugs-return-443277-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org>
Delivered-To: listarch-gcc-bugs@gcc.gnu.org
Received: (qmail 6458 invoked by alias); 11 Feb 2014 13:14:27 -0000
Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm
Precedence: bulk
List-Id: <gcc-bugs.gcc.gnu.org>
List-Archive: <http://gcc.gnu.org/ml/gcc-bugs/>
List-Post: <mailto:gcc-bugs@gcc.gnu.org>
List-Help: <mailto:gcc-bugs-help@gcc.gnu.org>
Sender: gcc-bugs-owner@gcc.gnu.org
Delivered-To: mailing list gcc-bugs@gcc.gnu.org
Received: (qmail 6392 invoked by uid 48); 11 Feb 2014 13:14:23 -0000
From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/60101] [4.7/4.8/4.9 Regression] Long compile times when mixed complex floating point datatypes are used in lengthy expressions
Date: Tue, 11 Feb 2014 13:14:00 -0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: c
X-Bugzilla-Version: 4.8.2
X-Bugzilla-Keywords: compile-time-hog, diagnostic
X-Bugzilla-Severity: normal
X-Bugzilla-Who: jakub at gcc dot gnu.org
X-Bugzilla-Status: NEW
X-Bugzilla-Priority: P2
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: 4.7.4
X-Bugzilla-Flags:
X-Bugzilla-Changed-Fields: cc
Message-ID: <bug-60101-4-R3wdzQGbDq@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-60101-4@http.gcc.gnu.org/bugzilla/>
References: <bug-60101-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 7bit
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
X-SW-Source: 2014-02/txt/msg01034.txt.bz2
Content-length: 506

http://gcc.gnu.org/bugzilla/show_bug.cgi?id`101

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |bernds at gcc dot gnu.org

--- Comment #9 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Ah, sorry, Manuel, it seems that code is older, has been added already in
http://gcc.gnu.org/ml/gcc-patches/2000-11/msg00541.html