-ftrapv is an implementation-provided flag that defines the behavior of some operations that are otherwise not defined by the language standard. The implementat

-ftrapv is an implementation-provided flag that defines the behavior of some operations that are otherwise not defined by the language standard. The implementation could define the behavior (under the same or different flags) to this newly introduced trap representation as well (no need to actually trap). Having said that this should be a new type, adding more UB to existing types is a bad idea.