benine203

libc++20 removes std::__compressed_pair; amend preprocessor directive

2

Conditionally protect against the offending code as stopgap. References issue #2351 If desired can try to use [`[[no_unique_address]]`](https://en.cppreference.com/w/cpp/language/attributes/no_unique_address) and `[[msvc::no_unique_address]]` where applicable.

https://github.com/facebook/folly/blob/abf77ba9340d7fb225c0a0fe6b355ca2a5652231/folly/memory/UninitializedMemoryHacks.h#L312 for instance references this From [libc++-20](https://github.com/llvm/llvm-project/blob/main/libcxx/include/__configuration/abi.h#L120-L125): ```cpp // Historically, libc++ used a type called `__compressed_pair` to reduce storage needs in cases of empty types (e.g. an // empty allocator...

Fails to build on recent libc++ (20 tested)

5

I tracked down this source file [Release/include/cpprest/streams.h](Release/include/cpprest/streams.h) ```cpp template struct Value2StringFormatter { template static std::basic_string format(const T& val) { std::basic_ostringstream ss; ss