Whether an explicit instantiation declaration should be provided is not
a matter of availability markup.
This problem is exemplified by the fact that some tests were incorrectly
marked as XFAIL when they should instead have been using the definition
of streams from the headers, and hence passing, and that, regardless of
whether visibility annotations are enabled.
llvm-svn: 348436
Libc++ is used as a system library on macOS and iOS (amongst others). In order
for users to be able to compile a binary that is intended to be deployed to an
older version of the platform, clang provides the
availability attribute <https://clang.llvm.org/docs/AttributeReference.html#availability>_
that can be placed on declarations to describe the lifecycle of a symbol in the
library.
See docs/DesignDocs/AvailabilityMarkup.rst for more information.
Differential Revision: https://reviews.llvm.org/D31739
llvm-svn: 302172
Louis Dionne