Erik Pilkington 1e36882b52 [ObjCARC] Add an new attribute, objc_externally_retained
This attribute, called "objc_externally_retained", exposes clang's
notion of pseudo-__strong variables in ARC. Pseudo-strong variables
"borrow" their initializer, meaning that they don't retain/release
it, instead assuming that someone else is keeping their value alive.

If a function is annotated with this attribute, implicitly strong
parameters of that function aren't implicitly retained/released in
the function body, and are implicitly const. This is useful to expose
for performance reasons, most functions don't need the extra safety
of the retain/release, so programmers can opt out as needed.

This attribute can also apply to declarations of local variables,
with similar effect.

Differential revision: https://reviews.llvm.org/D55865

llvm-svn: 350422
2019-01-04 18:33:06 +00:00
..
2018-12-03 22:51:07 +00:00
2018-11-29 14:57:14 +00:00
2018-12-04 14:34:09 +00:00

//===----------------------------------------------------------------------===//
// C Language Family Front-end
//===----------------------------------------------------------------------===//

Welcome to Clang.  This is a compiler front-end for the C family of languages
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