Extra Clang Tools 13.0.0 (In-Progress) Release Notes¶

Introduction
What’s New in Extra Clang Tools 13.0.0?

Written by the LLVM Team

Warning

These are in-progress notes for the upcoming Extra Clang Tools 13 release. Release notes for previous releases can be found on the Download Page.

Introduction ¶

This document contains the release notes for the Extra Clang Tools, part of the Clang release 13.0.0. Here we describe the status of the Extra Clang Tools in some detail, including major improvements from the previous release and new feature work. All LLVM releases may be downloaded from the LLVM releases web site.

For more information about Clang or LLVM, including information about the latest release, please see the Clang Web Site or the LLVM Web Site.

Note that if you are reading this file from a Git checkout or the main Clang web page, this document applies to the next release, not the current one. To see the release notes for a specific release, please see the releases page.

The run-clang-tidy.py helper script is now installed in bin/ as run-clang-tidy. It was previously installed in share/clang/.
Added command line option –fix-notes to apply fixes found in notes attached to warnings. These are typically cases where we are less confident the fix will have the desired effect.
libToolingCore and Clang-Tidy was refactored and now checks can produce highlights (^~~~~ under fragments of the source code) in diagnostics. Existing and new checks in the future can be expected to start implementing this functionality. This change only affects the visual rendering of diagnostics, and does not alter the behavior of generated fixes.

New checks ¶

New bugprone-implicit-widening-of-multiplication-result check.

Diagnoses instances of an implicit widening of multiplication result.
New concurrency-thread-canceltype-asynchronous check.

Finds pthread_setcanceltype function calls where a thread’s cancellation type is set to asynchronous.
New altera-id-dependent-backward-branch check.

Finds ID-dependent variables and fields that are used within loops. This causes branches to occur inside the loops, and thus leads to performance degradation.
New altera-unroll-loops check.

Finds inner loops that have not been unrolled, as well as fully unrolled loops with unknown loops bounds or a large number of iterations.
New cppcoreguidelines-prefer-member-initializer check.

Finds member initializations in the constructor body which can be placed into the initialization list instead.
New bugprone-unhandled-exception-at-new check.

Finds calls to new with missing exception handler for std::bad_alloc.

New check aliases ¶

New alias cert-pos47-c to concurrency-thread-canceltype-asynchronous was added.

Changes in existing checks ¶

Improved bugprone-signal-handler check.

Added an option to choose the set of allowed functions.
Improved readability-uniqueptr-delete-release check.

Added an option to choose whether to refactor by calling the reset member function or assignment to nullptr. Added support for pointers to std::unique_ptr.

Removed checks ¶

The readability-deleted-default check has been removed.

The clang warning Wdefaulted-function-deleted will diagnose the same issues and is enabled by default.

Extra Clang Tools 13 documentation