The changes applied by P3074R7 for C++26 alter existing well-defined behavior for template arguments. It is unclear whether such changes were design-intended. See CWG2999 for details. See also [P3726R0](https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2025/p3726r0.html) (Adjustments to Union Lifetime Rules) #2356.
