compiler_attributes.h: move __compiletime_{error|warning}

Clang 14 will add support for __attribute__((__error__(""))) and
__attribute__((__warning__(""))). To make use of these in
__compiletime_error and __compiletime_warning (as used by BUILD_BUG and
friends) for newer clang and detect/fallback for older versions of
clang, move these to compiler_attributes.h and guard them with
__has_attribute preprocessor guards.

Link: https://reviews.llvm.org/D106030
Link: https://bugs.llvm.org/show_bug.cgi?id=16428
Link: https://github.com/ClangBuiltLinux/linux/issues/1173
Signed-off-by: Nick Desaulniers <[email protected]>
Reviewed-by: Nathan Chancellor <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
[Reworded, landed in Clang 14]
Signed-off-by: Miguel Ojeda <[email protected]>

0 files changed, 0 insertions, 0 deletions