For C++ types that are defined in the bridging header, or are `#include`-d from the bridging header, we did not generate the automatic conformances to `CxxSequence`, `CxxRandomAccessCollection` protocols.
To check whether we should try to conform a C++ type to those protocols, the compiler checks for the presence of `requires cplusplus` in the module declaration in a modulemap file. This check is there to prevent us from accidentally pulling in `Cxx`/`CxxStdlib` modules when a client is importing a C library.
This change makes sure those conformances are generated.
rdar://121927459
`std::set::insert` isn't exposed into Swift, because it returns an instance of an unsafe type.
This change adds a Swift overload of `insert` for `std::set` and `std::unordered_set` that has the return type identical to `Swift.Set.insert`: a tuple of `(inserted: Bool, memberAfterInsert: Element)`.
rdar://111036912
This disables TBD validation when C++ interop is enabled, unless an explicit `-validate-tbd-against-ir=` flag was passed.
rdar://83405989 / https://github.com/apple/swift/issues/56458
This adds a protocol to the C++ standard library overlay which will improve the ergonomics of `std::set`, `std::unordered_set` and `std::multiset` when used from Swift code.
As of now, `CxxSet` adds a `contains` function to C++ sets.
C++ stdlib set types are automatically conformed to `CxxSet`: `std::set`, `unordered_set`, `std::multiset`. Custom user types are not conformed to `CxxSet` automatically: while a custom type might have an interface similar to `std::set`, the semantics might differ, and adding a conformance would cause confusion.
C++ iterator types are often templated, and sometimes declare `operator==` as a non-member templated function. In libc++, an example of this is `__wrap_iter` which is used as an iterator type for `std::vector` and `std::string`.
We don't currently import templated non-member operators into Swift, however, we still want to support common C++ iterator patterns.
This change adds logic to instantiate templated non-member `operator==` for types that define `iterator_category` and are therefore likely to be valid iterator types.
rdar://97915515
