Implement P2513
This change allows initializing an array of unsigned char,
or char from u8 string literals.
This was done both to support legacy code and for compatibility
with C where char8_t will be typedef to unsigned char.
This is backported to C++20 as per WG21 guidance.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D136449
This unfortunately results in a substantial breaking change when
switching to C++20, but it's not yet clear what / how much we should
do about that. We may want to add a compatibility conversion from
u8 string literals to const char*, similar to how C++98 provided a
compatibility conversion from string literals to non-const char*,
but that's not handled by this patch.
The feature can be disabled in C++20 mode with -fno-char8_t.
llvm-svn: 346892
This is not yet part of any C++ working draft, and so is controlled by the flag
-fchar8_t rather than a -std= flag. (The GCC implementation is controlled by a
flag with the same name.)
This implementation is experimental, and will be removed or revised
substantially to match the proposal as it makes its way through the C++
committee.
llvm-svn: 331244
Corentin Jabot