Re: c++/4871: value argument destructor called twice when a virtual method is called in virtual inherited class

Re: c++/4871: value argument destructor called twice when a virtual method is called in virtual inherited class

[jason]

Synopsis: value argument destructor called twice when a virtual method is called in virtual inherited class

State-Changed-From-To: open->feedback
State-Changed-By: jason
State-Changed-When: Tue Apr  9 10:16:33 2002
State-Changed-Why:
    I can't reproduce this with 3.0.4 or the current 3.1 branch; looks like it's been fixed.

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=4871

Re: c++/4871: value argument destructor called twice when a virtual method is called in virtual inherited class

[reichelt]

Synopsis: value argument destructor called twice when a virtual method is called in virtual inherited class

State-Changed-From-To: feedback->closed
State-Changed-By: reichelt
State-Changed-When: Sat Dec  7 13:53:58 2002
State-Changed-Why:
    Seems to be fixed.
    I checked gcc 3.0.4, 3.2.1 and mainline (3.3-20021118)

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=4871

c++/4871: value argument destructor called twice when a virtual method is called in virtual inherited class

[jamie]

>Number:         4871
>Category:       c++
>Synopsis:       value argument destructor called twice when a virtual method is called in virtual inherited class
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Nov 13 18:26:00 PST 2001
>Closed-Date:
>Last-Modified:
>Originator:     Jamie Painter <jamie@turboabs.com:>
>Release:        gcc version 3.0.2
>Organization:
>Environment:
Linux
>Description:
When a method is called with a class argument passed by value, under certain conditions the value is destructed twice.  The conditions seem to be related to the use of virtual inheritance, as demonstrated in the attached source.

>How-To-Repeat:
Compile (g++ gccbug.cpp), 
run (./a.out).

Observe the output:

constructing  ValueType 0xbffffa34
destructing   ValueType 0xbffffa34
destructing   ValueType 0xbffffa34

Note that the value parameter is constructed once and deconstructed twice.

Gcc 2.95.2 produces the correct output:

constructing  ValueType 0xbffff8a4
destructing   ValueType 0xbffff8a4

>Fix:

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