I'm not sure if the following should compile or not, but it certainly should ICE the compiler. Latest gcc from SVN with vararg template patches from Doug Gregor. Build with -std=c++0x.
Doug, no rush on this one. Just logging it for posterity. template<typename ... Args> struct foo { static bool const value = true; }; template<typename ... Args> struct foo< typename Args::is_applied... > { static bool const value = false; }; struct not_applied { typedef void is_applied; }; struct applied { typedef applied is_applied; }; int main() { foo<applied, applied> i; } -- Summary: internal compiler error: in dependent_type_p, at cp/pt.c:15319 (vararg templates) Product: gcc Version: 4.3.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: eric dot niebler at gmail dot com http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33964