https://godbolt.org/z/snjof8 The resolution of 1734 requires the class: - has at least one non-deleted copy constructor, move constructor, copy assignment operator, or move assignment operator, and - has a trivial, non-deleted destructor Therefore all 4 static-asserts should pass. Same bug in LLVM with discussion of ABI impact: https://bugs.llvm.org/show_bug.cgi?id=39050