[Bug c++/59922] New: -finstrument-functions emit false warning "control reaches end of non-void function"

[Bug c++/59922] New: -finstrument-functions emit false warning "control reaches end of non-void function"

[alex at alemate dot ru]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59922

            Bug ID: 59922
           Summary: -finstrument-functions emit false warning "control
                    reaches end of non-void function"
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: alex at alemate dot ru

Example input:

---------- t.c ---------
int something();                                                                

int f(int arg) {                                                                
 return 0;                                                                      
 (void)(false ? 1 : something());                                               
}   
-----------------------

$ c++ -c t.cc -finstrument-functions -Wall -Werror
t.cc: In function ‘int f(int)’:
t.cc:6:1: error: control reaches end of non-void function [-Werror=return-type]
 }
 ^
$ echo $?
1
$

But:

$ c++ -c t.cc -Wall -Werror
$ echo $?
0
$
>From gcc-bugs-return-441321-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org Thu Jan 23 16:20:53 2014
Return-Path: <gcc-bugs-return-441321-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org>
Delivered-To: listarch-gcc-bugs@gcc.gnu.org
Received: (qmail 18811 invoked by alias); 23 Jan 2014 16:20:53 -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 18752 invoked by uid 48); 23 Jan 2014 16:20:49 -0000
From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug ipa/59918] [4.9 Regression] ICE in record_target_from_binfo, at ipa-devirt.c:693
Date: Thu, 23 Jan 2014 16:20:00 -0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: ipa
X-Bugzilla-Version: 4.9.0
X-Bugzilla-Keywords:
X-Bugzilla-Severity: normal
X-Bugzilla-Who: jakub at gcc dot gnu.org
X-Bugzilla-Status: NEW
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags:
X-Bugzilla-Changed-Fields: cc
Message-ID: <bug-59918-4-2hHqbR6Lzr@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-59918-4@http.gcc.gnu.org/bugzilla/>
References: <bug-59918-4@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: 2014-01/txt/msg02463.txt.bz2
Content-length: 397

http://gcc.gnu.org/bugzilla/show_bug.cgi?idY918

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

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

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Started with r206543.

[Bug c++/59922] -finstrument-functions emit false warning "control reaches end of non-void function"

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59922

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
There is another bug about a similar thing but with
constructors/deconstructors.
-finstrument-functions inserts try/finally blocks in the code and the dead code
is not removed before hand so the warning mechanism gets confused.

[Bug c++/59922] -finstrument-functions emit false warning "control reaches end of non-void function"

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59922

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Related to bug 20681.