c++/240: problems with element templates, incl ICE

[r.spatschek@fz-juelich.de]

>Number:         240
>Category:       c++
>Synopsis:       problems with element templates, incl ICE
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed May 24 07:36:00 PDT 2000
>Closed-Date:
>Last-Modified:
>Originator:     Robert Spatschek
>Release:        gcc version egcs-2.91.66 19990314
>Organization:
>Environment:
SuSE Linux 6.3 Kernel 2.2.14
DEC alpha OSF1 4.0
>Description:
Several mysterious things happens with the code below:

1) comment out lines a, b, c, d (only e remains for simplicity)
call of nonexisting member function h of class A gives an ICE.
  [229] spatsche@iff645% gcc -o template1 template1.cpp
  template1.cpp: In function `int main()':
  template1.cpp:19: Internal compiler error.
  template1.cpp:19: Please submit a full bug report to `egcs-bugs@egcs.cygnus.com'.
  template1.cpp:19: See <URL: http://egcs.cygnus.com/faq.html#bugreport > for details.


2) comment out lines c, e (a, b, d remain)
linking doesn't work on DEC alpha OSF1:
  [226] spatsche@iff645% gcc -o template1 template1.cpp
  /bin/ld:
  Unresolved:
  cout
  ostream::operator<<(char const *)
  collect2: ld returned 1 exit status

Anyway, this combination works pretty well with Linux.


3) comment out line e (a, b, c, d remain)
call of A::f() works from the inside of the struct (see line b)
(of course again not on the DEC),
but compiler rejects line c:
  [227] spatsche@iff645% gcc -o template1 template1.cpp
  template1.cpp: In function `int main()':
  template1.cpp:17: parse error before `>'
For comparison: This works with the DEC C++ compiler.

Sorry that I decided to mention those three symptoms
together within one bug report.
>How-To-Repeat:
// template1.cpp
#include <iostream>

struct A
{
  template <class T> void f() {cout << "Hello\n";}   // line a
  void g() {f<int>();}                               // line b
};

template <class T> void h()
{
}

int main()
{
  A a;

  a.f<int>();     // line c
  a.g();          // line d
  a.h<int>();     // line e
}
>Fix:

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