[libcxx-commits] [libcxx] [libc++] Use public os_sync API instead of private __ulock on newer Apple platforms (PR #182947)

[Louis Dionne via libcxx-commits]

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@@ -15,18 +15,30 @@
 #    if __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ >= 101500
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ldionne wrote:

@Bbn08 

> This is a problem for anyone shipping apps through the App Store since Apple flags private symbol usage during review.

Just to understand, how is that flagged? This code shouldn't be included in your app since it is part of `libc++.dylib`, which is part of the system. Or are you including your own version of `libc++.a` inside your app that you built yourself? If that's the case, doing that is not a good idea since it could cause ODR violations. For example, libc++.dylib contains some global objects (e.g. `cin`) of which there must be a single copy in the whole process.

This doesn't change that I think we should switch to the public API, but I'd still like to better understand your setup.

https://github.com/llvm/llvm-project/pull/182947