624b724ca6
For backwards compatibility reasons the `ptrauth_qualifier` and `ptrauth_intrinsic` features need to be testable with `__has_feature()` on Apple platforms, but for other platforms this backwards compatibility issue does not exist. This PR resolves these issues by making the `ptrauth_qualifier` and `ptrauth_intrinsic` tests conditional upon a darwin target. This also allows us to revert the ptrauth_qualifier check from an extension to a feature test again, as is required on these platforms. At the same time we introduce a new predefined macro `__PTRAUTH__` that answers the same question as `__has_feature(ptrauth_qualifier)` and `__has_feature(ptrauth_intrinsic)` as those tests are synonymous and only exist separately for compatibility reasons. The requirement to test for the `__PTRAUTH__` macro also resolves the hazard presented by mixing the `ptrauth_qualifier` flag (that impacts ABI and security policies) with `-pedantics-errors`, which makes `__has_extension` return false for all extensions. --------- Co-authored-by: Aaron Ballman <aaron@aaronballman.com>
C language Family Front-end
Welcome to Clang.
This is a compiler front-end for the C family of languages (C, C++ and Objective-C) which is built as part of the LLVM compiler infrastructure project.
Unlike many other compiler frontends, Clang is useful for a number of things beyond just compiling code: we intend for Clang to be host to a number of different source-level tools. One example of this is the Clang Static Analyzer.
If you're interested in more (including how to build Clang) it is best to read the relevant websites. Here are some pointers:
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Information on Clang: http://clang.llvm.org/
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Building and using Clang: http://clang.llvm.org/get_started.html
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Clang Static Analyzer: http://clang-analyzer.llvm.org/
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Information on the LLVM project: http://llvm.org/
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If you have questions or comments about Clang, a great place to discuss them is on the Clang forums:
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If you find a bug in Clang, please file it in the LLVM bug tracker: