Summary:
This commit adopts the exclude_from_explicit_instantiation attribute discussed
at [1] and reviewed in [2] in libc++ to supplant the use of __always_inline__
for visibility purposes.
This change means that users wanting to link together translation units built
with different versions of libc++'s headers into the same final linked image
MUST define the _LIBCPP_HIDE_FROM_ABI_PER_TU macro to 1 when building those
TUs. Doing otherwise will lead to ODR violations and ABI issues.
[1]: http://lists.llvm.org/pipermail/cfe-dev/2018-August/059024.html
[2]: https://reviews.llvm.org/D51789
Reviewers: rsmith, EricWF
Subscribers: dexonsmith, libcxx-commits
Differential Revision: https://reviews.llvm.org/D52405
llvm-svn: 345516
libc++ has dropped support for Mac OS 10.6 for a while, and we don't
have any testers set up for that OS.
This commit puts in an error message so that people can reach out to
the libc++ maintainers in case support for 10.6 is still expected (as
opposed to silently failing in weird ways). We can completely drop
support for 10.6 and remove the error message some time in the future
when we're sure that nobody is relying on it.
llvm-svn: 344576