Author: Jan Voung Date: 2025-02-27T10:35:24-05:00 New Revision: eeb672a47c59b1d94ea3198d7427314ebbd80777
URL: https://github.com/llvm/llvm-project/commit/eeb672a47c59b1d94ea3198d7427314ebbd80777 DIFF: https://github.com/llvm/llvm-project/commit/eeb672a47c59b1d94ea3198d7427314ebbd80777.diff LOG: [clang-tidy] Add a release note about unchecked-optional-access smart pointer caching (#122290) With caching added in https://github.com/llvm/llvm-project/pull/120249, the `IgnoreSmartPointerDereference` option shouldn't be needed anymore. Other caching also added earlier: https://github.com/llvm/llvm-project/pull/112605 Added: Modified: clang-tools-extra/docs/ReleaseNotes.rst clang-tools-extra/docs/clang-tidy/checks/bugprone/unchecked-optional-access.rst Removed: ################################################################################ diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst index 1a68a3d182e04..a8d17d19fda1d 100644 --- a/clang-tools-extra/docs/ReleaseNotes.rst +++ b/clang-tools-extra/docs/ReleaseNotes.rst @@ -108,6 +108,12 @@ Changes in existing checks calls of ``std::string`` constructor with char pointer, start position and length parameters. +- Improved :doc:`bugprone-unchecked-optional-access + <clang-tidy/checks/bugprone/unchecked-optional-access>` fixing false + positives from smart pointer accessors repeated in checking ``has_value`` + and accessing ``value``. The option `IgnoreSmartPointerDereference` should + no longer be needed and will be removed. + - Improved :doc:`bugprone-unsafe-functions <clang-tidy/checks/bugprone/unsafe-functions>` check to allow specifying additional C++ member functions to match. diff --git a/clang-tools-extra/docs/clang-tidy/checks/bugprone/unchecked-optional-access.rst b/clang-tools-extra/docs/clang-tidy/checks/bugprone/unchecked-optional-access.rst index 815b5cdeeebe2..552e6db699696 100644 --- a/clang-tools-extra/docs/clang-tidy/checks/bugprone/unchecked-optional-access.rst +++ b/clang-tools-extra/docs/clang-tidy/checks/bugprone/unchecked-optional-access.rst @@ -71,8 +71,8 @@ For example: .. code-block:: c++ void f(Foo foo) { - if (foo.opt().has_value()) { - use(*foo.opt()); // unsafe: it is unclear whether `foo.opt()` has a value. + if (foo.take().has_value()) { + use(*foo.take()); // unsafe: it is unclear whether `foo.take()` has a value. } } @@ -81,10 +81,11 @@ Exception: accessor methods The check assumes *accessor* methods of a class are stable, with a heuristic to determine which methods are accessors. Specifically, parameter-free ``const`` -methods are treated as accessors. Note that this is not guaranteed to be safe --- but, it is widely used (safely) in practice, and so we have chosen to treat -it as generally safe. Calls to non ``const`` methods are assumed to modify -the state of the object and affect the stability of earlier accessor calls. +methods and smart pointer-like APIs (non ``const`` overloads of ``*`` when +there is a parallel ``const`` overload) are treated as accessors. Note that +this is not guaranteed to be safe -- but, it is widely used (safely) in +practice. Calls to non ``const`` methods are assumed to modify the state of +the object and affect the stability of earlier accessor calls. Rely on invariants of uncommon APIs ----------------------------------- @@ -191,14 +192,15 @@ paths that lead to an access. For example: Stabilize function results ~~~~~~~~~~~~~~~~~~~~~~~~~~ -Since function results are not assumed to be stable across calls, it is best to -store the result of the function call in a local variable and use that variable -to access the value. For example: +Function results are not assumed to be stable across calls, except for +const accessor methods. For more complex accessors (non-const, or depend on +multiple params) it is best to store the result of the function call in a +local variable and use that variable to access the value. For example: .. code-block:: c++ void f(Foo foo) { - if (const auto& foo_opt = foo.opt(); foo_opt.has_value()) { + if (const auto& foo_opt = foo.take(); foo_opt.has_value()) { use(*foo_opt); } } _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
