Testcase: struct Array(T) { size_t dim; T* data; } extern(C++) void foo(Array!int arr) { } Currently ICE's at: dfrontend/cppmangle.c:154: void CppMangleVisitor::cpp_mangle_name(Dsymbol*): Assertion `0' failed. This should be fixed for DDMD support.
Support was added a while ago. https://github.com/D-Programming-GDC/GDC/pull/131