Re: c++/7105: g++ 2.95.3 misses candidate function in virtual base of class template

Re: c++/7105: g++ 2.95.3 misses candidate function in virtual base of class template

[nathan]

Synopsis: g++ 2.95.3 misses candidate function in virtual base of class template

State-Changed-From-To: open->closed
State-Changed-By: nathan
State-Changed-When: Sat Sep 14 14:16:45 2002
State-Changed-Why:
    fixed in cvs

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=7105

c++/7105: g++ 2.95.3 misses candidate function in virtual base of class template

[cludwig]

>Number:         7105
>Category:       c++
>Synopsis:       g++ 2.95.3 misses candidate function in virtual base of class template
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          rejects-legal
>Submitter-Id:   net
>Arrival-Date:   Mon Jun 24 06:36:01 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator:     lidiaadm@cdc.informatik.tu-darmstadt.de
>Release:        2.95.3 20010315 (SuSE)
>Organization:
>Environment:
SuSE Linux 7.3, kernel 2.4.10-4GB, i386
>Description:
g++ 2.95.3 / Linux / i386 fails to compile the attached 
file with the following error message:

  cludwig@cdcNT42:~/C++/gcc2/tmp> g++  -o bugtest bugtest.cc 
  bugtest.cc: In method `void B<int>::foo()':
  bugtest.cc:59:   instantiated from here
  bugtest.cc:54: no match for `B<int> & = A<int> &'
  bugtest.cc:20: candidates are: class B<int> & B<int>::operator =(const B<int> &)

I expect line 54 to expand to 
  *this = B<T>(a);
so there is only one user defined conversion involved. 
Therefore, the code is legal.

g++ 3.0.3 / Linux / i386 as well as 
g++ 2.95.2 / Solaris 8 / sparc compile the example without
error or warning.

The problem shows only if 
 * A is a class template and 
 * A is a *virtual* base class of B.

Best regards

Christoph Ludwig
>How-To-Repeat:
g++ -o bugtest bugtest.cc
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
----gnatsweb-attachment----
Content-Type: application/octet-stream; name="bugtest.cc"
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="bugtest.cc"

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