c++/3671: g++ incorrectly tries to instantiate multiple member template specializations

[weissr at informatik dot uni-tuebingen dot de]

>Number:         3671
>Category:       c++
>Synopsis:       g++ incorrectly tries to instantiate multiple member template specializations
>Confidential:   no
>Severity:       critical
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          rejects-legal
>Submitter-Id:   net
>Arrival-Date:   Fri Jul 13 03:26:00 PDT 2001
>Closed-Date:
>Last-Modified:
>Originator:     Roland Weiss
>Release:        gcc version 3.0
>Organization:
>Environment:
i686-pc-linux-gnu, Linux Mandrake 8.0
>Description:
g++ emits the following error message when compiling my test program:

Dependent_Types_Specialization.cpp: In function `int main()':
Dependent_Types_Specialization.cpp:79: cannot convert `Index2' to `Index1' in
   initialization
Dependent_Types_Specialization.cpp:79: non-constant `<expression error>' cannot
   be used as template argument

The problems seems to be that g++ incorrectly tries to instantiate both versions of the get_index member template in the class template Compound_Type. Therefore the index_type given at the instantiation place in the main program will not match one version and trigger the error message.

The program compiles without problems using the EGD frontend 2.44.
>How-To-Repeat:
run g++ on the file Dependent_Types_Specialization.cpp, no special flags are needed
>Fix:
don't know one!
>Release-Note:
>Audit-Trail:
>Unformatted:
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