Author: Zixu Wang Date: 2024-02-16T05:36:18-08:00 New Revision: ddc2a5ff4e149d07fcda735c1d860be95006fe2a
URL: https://github.com/llvm/llvm-project/commit/ddc2a5ff4e149d07fcda735c1d860be95006fe2a DIFF: https://github.com/llvm/llvm-project/commit/ddc2a5ff4e149d07fcda735c1d860be95006fe2a.diff LOG: [18.x][Docs] Add release note about Clang-defined target OS macros (#80044) The change is included in the 18.x release. Move the release note to the release branch and reformat. (cherry picked from commit b40d5b1b08564d23d5e0769892ebbc32447b2987) Added: Modified: clang/docs/ReleaseNotes.rst Removed: ################################################################################ diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 9edbfbfbbac02e..93a67e7a895592 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -171,6 +171,22 @@ AST Dumping Potentially Breaking Changes "qualType": "foo" } +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 @@ -351,6 +367,15 @@ New Compiler Flags * Full register names can be used when printing assembly via ``-mregnames``. This option now matches the one used by GCC. +.. _target_os_detail: + +* ``-fdefine-target-os-macros`` and its complement + ``-fno-define-target-os-macros``. Enables or disables the Clang 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 ------------------------- _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
