Kenneth Moreland 4a7aae86f9 Allow Variant to be trivial ... Although `vtkm::internal::Variant` respected the trivially copyable attribute of the types it contains, it was never totally trivial (i.e. `std::is_trivial<Variant<...>>` was never true). The reason was that `Variant` was initializing its `Index` parameter to signify that it was not initialized. However, the fact that `Index` was initialized meant that it was not trivially constructed. Now, `Variant` type checks its types to see if they are all trivially constructible. If so, it makes itself trivially constructible. This means that `Index` may or may not be valid if `Variant` is constructed without an argument. This in turn means that the result of `Variant::IsValid` becomes undefined. That should be OK in practice. `Index` will "point" to an uninitialized object, but that object is trivially constructed anyway. However, that could cause problems if developers used `IsValid` to determine if something is selected.		2020-09-22 16:22:37 -06:00
..
aligned_union.h	Add porting layer for future std features	2020-03-16 17:12:16 -06:00
CMakeLists.txt	Allow Variant to be trivial	2020-09-22 16:22:37 -06:00
integer_sequence.h	clang-format: reformat the repository with clang-format-9	2020-08-24 14:01:08 -04:00
is_trivial.h	Allow Variant to be trivial	2020-09-22 16:22:37 -06:00
void_t.h	Add porting layer for future std features	2020-03-16 17:12:16 -06:00