The following invalid code snippet is accepted (since at least gcc 2.95.3). It is rejected when A gets instantiated, but that could be diagnosed at definition time IMHO.
=========================== template<int> struct A { ~A() {} ~A() {} }; =========================== -- Summary: Duplicate destructor accepted Product: gcc Version: 4.0.0 Status: UNCONFIRMED Keywords: accepts-invalid, monitored Severity: normal Priority: P2 Component: c++ AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: reichelt at gcc dot gnu dot org CC: gcc-bugs at gcc dot gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19439