llvm-project/clang/test/SemaObjC/externally-retained-no-arc.m

// RUN: %clang_cc1 %s -verify

@interface NSWidget @end

__attribute__((objc_externally_retained)) void f(NSWidget *p) { // expected-warning{{'objc_externally_retained' attribute ignored}}
  __attribute__((objc_externally_retained)) NSWidget *w; // expected-warning{{'objc_externally_retained' attribute ignored}}
}
[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 2019-01-05 02:33:06 +08:00			`// RUN: %clang_cc1 %s -verify`

			`@interface NSWidget @end`

			`__attribute__((objc_externally_retained)) void f(NSWidget *p) { // expected-warning{{'objc_externally_retained' attribute ignored}}`
			`__attribute__((objc_externally_retained)) NSWidget *w; // expected-warning{{'objc_externally_retained' attribute ignored}}`
			`}`