Re: c++/5270: MI + virtual base: segfault when throwing an exception in a derived ctor

Re: c++/5270: MI + virtual base: segfault when throwing an exception in a derived ctor

[rodrigc]

Synopsis: MI + virtual base: segfault when throwing an exception in a derived ctor

State-Changed-From-To: open->closed
State-Changed-By: rodrigc
State-Changed-When: Sun Mar 24 14:55:30 2002
State-Changed-Why:
    Problem reproduced with gcc 3.0.4.
    
    Problem does not occur with gcc 3.1 20020322 (prerelease)

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=5270

c++/5270: MI + virtual base: segfault when throwing an exception in a derived ctor

[daniel.elstner]

>Number:         5270
>Category:       c++
>Synopsis:       MI + virtual base: segfault when throwing an exception in a derived ctor
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          wrong-code
>Submitter-Id:   net
>Arrival-Date:   Thu Jan 03 18:46:01 PST 2002
>Closed-Date:
>Last-Modified:
>Originator:     Daniel Elstner
>Release:        gcc version 3.0.4 20020103 (prerelease)
>Organization:
>Environment:
i686-pc-linux-gnu
>Description:
Scenario:  A particular inheritance construct involving MI and one virtual base class (for further details please look at the test case).  When the ctor of the most-derived class throws an exception, the program receives a SIGSEGV.

The problem seems to occur only if both base classes, the virtual and the non-virtual one, have a virtual dtor.  I was also able to reproduce (the closed) PR #2276, which seems to be the same issue.

The segfault is reproduceable with gcc releases 3.0.2, 3.0.3, and CVS 3.0.4 20020103.  It works fine with 2.95.4 20010319 and RedHat's 2.96 (don't know the exact revision).
>How-To-Repeat:
g++ -o test-ctor-throw test-ctor-throw.cc
./test-ctor-throw

It should print "exception caught: foobar" if it works.  Using the gcc versions mentioned in the PR description, it receives a segmentation fault.
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
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