llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang Author: Zixu Wang (zixu-w) <details> <summary>Changes</summary> --- Full diff: https://github.com/llvm/llvm-project/pull/79879.diff 1 Files Affected: - (modified) clang/docs/ReleaseNotes.rst (+29) ``````````diff diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 05c42f8485d4ee3..29377f9537e88f7 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -49,6 +49,24 @@ ABI Changes in This Version AST Dumping Potentially Breaking Changes ---------------------------------------- +Clang Frontend Potentially Breaking Changes +------------------------------------------- + +Target OS macros extension +^^^^^^^^^^^^^^^^^^^^^^^^^^ +A new Clang extension (see :ref:`here <target_os_detail>`) is enabled for +Darwin (Apple platform) targets. Clang now defines ``TARGET_OS_*`` macros for +these targets, which could break existing code bases with improper checks for +the ``TARGET_OS_`` macros. For example, existing checks might fail to include +the ``TargetConditionals.h`` header from Apple SDKs and therefore leaving the +macros undefined and guarded code unexercised. + +Affected code should be checked to see if it's still intended for the specific +target and fixed accordingly. + +The extension can be turned off by the option ``-fno-define-target-os-macros`` +as a workaround. + What's New in Clang |release|? ============================== Some of the major new features and improvements to Clang are listed @@ -83,6 +101,17 @@ Non-comprehensive list of changes in this release New Compiler Flags ------------------ +.. _target_os_detail: + +Target OS macros extension +^^^^^^^^^^^^^^^^^^^^^^^^^^ +A pair of new flags ``-fdefine-target-os-macros`` and +``-fno-define-target-os-macros`` has been added to Clang to enable/disable the +extension to provide built-in definitions of a list of ``TARGET_OS_*`` macros +based on the target triple. + +The extension is enabled by default for Darwin (Apple platform) targets. + Deprecated Compiler Flags ------------------------- `````````` </details> https://github.com/llvm/llvm-project/pull/79879 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits