https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86305
--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> --- > g++ segfaults when compiling template member function that calls destructo No it doesn't! > A previous version of clang++ produces similar error > messages:https://bugs.llvm.org/show_bug.cgi?id=30361 This doesn't look similar to me: $ clang++ -c test.cpp Unable to find instantiation of declaration! UNREACHABLE executed at llvm/tools/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp:4897! Please make more of an effort to post useful bug reports, I am tired of wasting my time trying to understand the nonsense you write here.