The arm64 ABI used by FreeBSD (perhaps Linux and Android too) has the C type 'long double' mapped to a 128-bit floating point type. Full interoperability between Swift and C on platforms with 128-bit floating point type cannot be achieved unless Swift has such a type.
What would it take to add Float128 to the Swift standard library?
- Is writing a Swift evolution proposal the first step one needs to take?
- How difficult would it be? Clang and LLVM already have support for 128-bit floating point.
- Can you have the type Float128 added to the standard library if it will be implemented on some platforms only?