In 3.4.4 under Cygwin (but not under 3.4.0 and Debian GNU/Linux) the following
situation causes "duplicate definition" linker errors:
1) A template class has a static data member:
template<typename T> struct foo { static T t; };
2) The static member is template-defined at file scope in one module:
template<typename T> T foo<T>::t = 0;
3) And also defined in the anonymous namespace in another module:
namespace { template<typename T> T foo<T>::t = 0; }
4) The template itself is instantiated in the namespace in the same module:
namespace { foo<int> f; }
5) and also at file scope in some other module:
foo<int> g;
then the linker produces "multiple definition" messages for the static member.
I am not sure whether collect2 is instantiating the same template twice, or
whether it is instantiating each of the two templates once each but is not
qualifying the name of the anonymous version with the namespace name.
--
Summary: Template instantiated twice
Product: gcc
Version: 3.4.4
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: igodard at pacbell dot net
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25748
