c++/10804: regression from 3.2: implicit instantiation of template static methods

[harinath at cs dot umn dot edu]

>Number:         10804
>Category:       c++
>Synopsis:       regression from 3.2: implicit instantiation of template static methods
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu May 15 16:36:00 UTC 2003
>Closed-Date:
>Last-Modified:
>Originator:     harinath@cs.umn.edu
>Release:        gcc version 3.4 20030512 (experimental)
>Organization:
>Environment:
i686-pc-linux-gnu
>Description:
Linking fails on the following file:

--8<--
template<class T>
struct A
{
  A() { const void (*a)() = foo; }
  static const void foo() {}
};

int main(int argc, char *argv[])
{
  A<int> a;
}
--8<--

with the error:
/tmp/ccube68X.o(.gnu.linkonce.t._ZN1AIiEC1Ev+0x9): In function `A<int>::A[in-charge]()':
: undefined reference to `A<int>::foo()'
collect2: ld returned 1 exit status

There is no problem with GCC 3.2.
>How-To-Repeat:
c++ implicit-instantiation.cc

Here's the output of nm with GCC 3.4:

         U A<int>::foo()
00000000 W A<int>::A[in-charge]()
00000000 T main

and here's the output with GCC 3.2

00000000 W A<int>::foo()
00000000 W A<int>::A[in-charge]()
         U __gxx_personality_v0
00000000 T main

Notice that GCC 3.4 did DTRT with the constructor.  If I replace the use of foo in the code with a direct method call, then there's no problem either.
>Fix:

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