Re: c++/7400: segfault with -shared option

Re: c++/7400: segfault with -shared option

[bangerth]

Synopsis: segfault with -shared option

State-Changed-From-To: analyzed->closed
State-Changed-By: bangerth
State-Changed-When: Wed Oct 30 15:35:57 2002
State-Changed-Why:
    Michael's right, of course. How stupid...

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=7400

Re: c++/7400: segfault with -shared option

[David Jung]

The following reply was made to PR c++/7400; it has been noted by GNATS.

From: David Jung <jungdl@ornl.gov>
To: gcc-gnats@gcc.gnu.org, gcc-prs@gcc.gnu.org, gcc-bugs@gcc.gnu.org,
   nobody@gcc.gnu.org, t6@pobox.com
Cc:  
Subject: Re: c++/7400: segfault with -shared option
Date: 31 Oct 2002 10:18:46 -0500

 http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view audit-trail
 
 Michael Matz <matz@suse.de> wrote:
 > Huh?  With -shared you create a shared library.  You can't run a shared
 > lib.  So getting a SEGV isn't wrong.
 
 Yep.  You're right.  My original problem was not in trying to
 run a shared lib, but in my effort to reduce the problem report
 to the minimum reproducible code, I obviously got a bit
 overzealous.  Sorry about that.
 I don't know if my original problem is fixed in 3.2, as the code
 was redesigned to eliminate the dynamic_casts that were causing
 the problem.
 So I guess you can close it.  If I come across it again I'll reopen
 or post another report.
 Thanks.
 
 

Re: c++/7400: segfault with -shared option

[Wolfgang Bangerth]

The following reply was made to PR c++/7400; it has been noted by GNATS.

From: Wolfgang Bangerth <bangerth@ticam.utexas.edu>
To: Michael Matz <matz@suse.de>
Cc: gcc-bugs@gcc.gnu.org, <gcc-prs@gcc.gnu.org>, <nobody@gcc.gnu.org>,
   <t6@pobox.com>, <gcc-gnats@gcc.gnu.org>
Subject: Re: c++/7400: segfault with -shared option
Date: Wed, 30 Oct 2002 17:38:32 -0600 (CST)

 > >     ------------------------------
 > >     int main () {};
 > >     ------------------------------
 > >
 > >     Here's what I get:
 > >     tmp/g> c++ -shared x.cc
 > >     tmp/g> ./a.out
 > >     Speicherzugriffsfehler
 > 
 > Huh?  With -shared you create a shared library.  You can't run a shared
 > lib.  So getting a SEGV isn't wrong.
 
 Very fair criticism. I was just confused that I could execute the library, 
 and that I could also open it in gdb like a program.
 
 Thanks for lifting the bar from in front of my head :-) I'll close the 
 report in a second.
 
 Regards
   Wolfgang
 
 -------------------------------------------------------------------------
 Wolfgang Bangerth              email:           bangerth@ticam.utexas.edu
                                www: http://www.ticam.utexas.edu/~bangerth
 
 

Re: c++/7400: segfault with -shared option

[Michael Matz]

The following reply was made to PR c++/7400; it has been noted by GNATS.

From: Michael Matz <matz@suse.de>
To: <bangerth@dealii.org>, <gcc-bugs@gcc.gnu.org>,
	<gcc-prs@gcc.gnu.org>, <nobody@gcc.gnu.org>, <t6@pobox.com>,
	<gcc-gnats@gcc.gnu.org>
Cc:  
Subject: Re: c++/7400: segfault with -shared option
Date: Thu, 31 Oct 2002 00:17:18 +0100 (CET)

 Hi,
 
 On 30 Oct 2002 bangerth@dealii.org wrote:
 
 >     I see the same behavior, although it has nothing to do with
 >     dynamic_cast as suggested in the previous name of the
 >     report: this also happens with this code:
 >     ------------------------------
 >     int main () {};
 >     ------------------------------
 >
 >     Here's what I get:
 >     tmp/g> c++ x.cc
 >     tmp/g> ./a.out
 >     tmp/g>
 >     tmp/g> c++ -shared x.cc
 >     tmp/g> ./a.out
 >     Speicherzugriffsfehler
 >     (which means "Segmentation Fault", I just have not found
 >     out how to change the stupid german defaults on my system.)
 
 Huh?  With -shared you create a shared library.  You can't run a shared
 lib.  So getting a SEGV isn't wrong.
 
 
 Ciao,
 Michael.
 

Re: c++/7400: segfault with -shared option

[bangerth]

Old Synopsis: dynamic_cast segfaults with -shared option
New Synopsis: segfault with -shared option

State-Changed-From-To: open->analyzed
State-Changed-By: bangerth
State-Changed-When: Wed Oct 30 15:03:03 2002
State-Changed-Why:
    I see the same behavior, although it has nothing to do with
    dynamic_cast as suggested in the previous name of the 
    report: this also happens with this code:
    ------------------------------
    int main () {};
    ------------------------------
    
    Here's what I get:
    tmp/g> c++ x.cc
    tmp/g> ./a.out
    tmp/g>
    tmp/g> c++ -shared x.cc
    tmp/g> ./a.out
    Speicherzugriffsfehler
    (which means "Segmentation Fault", I just have not found
    out how to change the stupid german defaults on my system.)
    
    I guess I must be making something very naive, but then
    I don't see it, and this happens with 2.95, 3.2 and present
    CVS... :-(
    
    (And no, I don't have any idea why I can compile all my
    program with this option and why it runs. Also, the
    problem does not go away if I use -fPIC, or if I link
    separately. The crash happens before we get into "main",
    by the way, and we don't get a meaningful backtrace. Please
    someone enlighten me...)

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=7400