This commit reverts 5aaefa51 (and also partly 7f285f48e7 and b6d75682f9,
which were related to the original commit). As landed, 5aaefa51 had
unintended consequences on some downstream bots and didn't have proper
coverage upstream due to a few subtle things. Implementing this is
something we should do in libc++, however we'll first need to address
a few issues listed in https://reviews.llvm.org/D106124#3349710.
Differential Revision: https://reviews.llvm.org/D120683
libc++ has started splicing standard library headers into much more
fine-grained content for maintainability. It's very likely that outdated
and naive tooling (some of which is outside of LLVM's scope) will
suggest users include things such as <__ranges/access.h> instead of
<ranges>, and Hyrum's law suggests that users will eventually begin to
rely on this without the help of tooling. As such, this commit
intends to protect users from themselves, by making it a hard error for
anyone outside of the standard library to include libc++ detail headers.
Differential Revision: https://reviews.llvm.org/D106124
This move the helper types `chars_format`, `to_chars_result` and
`from_chars_result` to a separate header. The first two are needed for
D70631 the third for consistency.
The header `__charconv/ryu.h` uses these types and it can't depend on the
types in `<charconv>` in a modular build. Moving them to the ryu header
would be an odd place and doesn't work since the header is included in the
middle of `<charconv>`.
Reviewed By: #libc, ldionne, Quuxplusone
Differential Revision: https://reviews.llvm.org/D108927
Louis Dionne