================ @@ -0,0 +1,77 @@ +//===--- ConflictingGlobalAccesses.h - clang-tidy ---------------*- C++ -*-===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_SIDEEFFECTBETWEENSEQUENCE\ +POINTSCHECK_H +#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_SIDEEFFECTBETWEENSEQUENCE\ +POINTSCHECK_H + +#include "../ClangTidyCheck.h" + +namespace clang::tidy::bugprone { + +/// Finds conflicting accesses on global variables. +/// +/// Modifying twice or reading and modifying a memory location without a +/// defined sequence of the operations is undefined behavior. This checker is +/// similar to the -Wunsequenced clang warning, however it only looks at global +/// variables and can find unsequenced operations inside functions as well. +/// +/// For example: \code +/// +/// int a = 0; +/// int b = (a++) - a; // This is flagged by -Wunsequenced. +/// +/// \endcode +/// +/// However global variables allow for more complex scenarios that +/// -Wunsequenced doesn't detect. E.g. \code +/// +/// int globalVar = 0; +/// +/// int incFun() { +/// globalVar++; +/// return globalVar; +/// } +/// +/// int main() { +/// return globalVar + incFun(); // This is not detected by -Wunsequenced. +/// } +/// +/// \endcode +/// +/// This checker attempts to detect such undefined behavior. It recurses into +/// functions that are inside the same translation unit. It also attempts not to +/// flag cases that are already covered by -Wunsequenced. Global unions and +/// structs are also handled. +/// +/// It's possible to enable handling mutable reference and pointer function +/// parameters as writes using the HandleMutableFunctionParametersAsWrites +/// option. For example: \code +/// +/// void func(int& a); +/// +/// int globalVar; +/// func(globalVar); // <- this could be a write to globalVar. +/// +/// \endcode +/// +/// This option is disabled by default. ---------------- PiotrZSL wrote:
this should be in documentation file, not here https://github.com/llvm/llvm-project/pull/130421 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
