Re: c++/4973: weird template instantiation

Re: c++/4973: weird template instantiation

[nathan]

Synopsis: weird template instantiation

State-Changed-From-To: open->closed
State-Changed-By: nathan
State-Changed-When: Sun Sep 15 12:35:24 2002
State-Changed-Why:
    not a bug. Net<5>::SubNet requires instantiating Net<5>
    (to see what SubNet turns out to be). That instantiates the
    interface of all Net<5>'s functions, which includes
    Net(typename Net<D+1>::SubNet const &), and
    so it'll never terminate

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=4973

c++/4973: weird template instantiation

[benko]

>Number:         4973
>Category:       c++
>Synopsis:       weird template instantiation
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Nov 30 00:56:01 PST 2001
>Closed-Date:
>Last-Modified:
>Originator:     Pal Benko
>Release:        3.0.2
>Organization:
>Environment:
SuSE7.1, i686
>Description:
Compiling the attached program I got

arta:~/c/proba$ /gml/shared/gcc-3.0.2/bin/g++ -Wall -ftemplate-depth-3 templit.cc
templit.cc:20: template instantiation depth exceeds maximum of 3 (use 
   -ftemplate-depth-NN to increase the maximum) instantiating `struct Net<8>'
templit.cc:20:   instantiated from `Net<7>'
templit.cc:20:   instantiated from `Net<6>'
templit.cc:20:   instantiated from `Net<5>'
templit.cc:26:   instantiated from here
templit.cc:20: invalid use of undefined type `struct Net<8>'
templit.cc:3: forward declaration of `struct Net<8>'
templit.cc: In function `int main()':
templit.cc:27: warning: unused variable `Net<4> n'
zsh: exit 1     /gml/shared/gcc-3.0.2/bin/g++ -Wall -ftemplate-depth-3 templit.cc

I think instantiating Net<7> should not be attempted.
>How-To-Repeat:

>Fix:

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