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Re: property 'atomic' keyword?
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Re: property 'atomic' keyword?



> If you'd like to reason about or conditionalize your code on various language features, please use the Clang feature checking macros:
> http://clang.llvm.org/docs/LanguageExtensions.html#feature_check
>
> For some Objective-C examples:
> http://clang.llvm.org/docs/LanguageExtensions.html#objc_features

Is there a feature checking macro `__has_feature` or `__has_extension` that we can use to determine whether `atomic` is an accepted property attribute keyword? I couldn’t find one in <http://clang.llvm.org/docs/LanguageExtensions.html#feature_check> or <https://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Lex/PPMacroExpansion.cpp>.

I’m turning this warning on in my projects and am looking for a better way to detect it’s availability than a `defined(__clang__) && __clang_major__ >= 4` preprocessor check. If there isn’t one currently I’ll happily file a bug.

From what I can tell the parser accepts a trailing comma in an `@property` attribute list so you can use a macro that expands to nothing if unsupported and leaves a trailing comma after the last attribute.

Cheers,
Keith


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