================ @@ -0,0 +1,67 @@ +//===--- ExceptionRethrowCheck.cpp - clang-tidy ---------------------------===// +// +// 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 +// +//===----------------------------------------------------------------------===// + +#include "ExceptionRethrowCheck.h" +#include "clang/ASTMatchers/ASTMatchFinder.h" +#include "clang/ASTMatchers/ASTMatchers.h" + +using namespace clang::ast_matchers; + +namespace clang::tidy::bugprone { + +void ExceptionRethrowCheck::registerMatchers(MatchFinder *Finder) { + + auto RefToExceptionVariable = declRefExpr(to(varDecl(isExceptionVariable()))); + auto StdMoveCall = + callExpr(argumentCountIs(1), callee(functionDecl(hasName("::std::move"))), + hasArgument(0, RefToExceptionVariable)); + auto CopyOrMoveConstruction = cxxConstructExpr( + argumentCountIs(1), + traverse(TK_AsIs, hasDeclaration(cxxConstructorDecl( + anyOf(isCopyConstructor(), isMoveConstructor())))), + hasArgument(0, anyOf(RefToExceptionVariable, StdMoveCall))); + + auto HasEmptyThrowExprDescendant = + hasDescendant(cxxThrowExpr(equalsBoundNode("empty-throw"))); + + Finder->addMatcher( + cxxThrowExpr( + unless(isExpansionInSystemHeader()), unless(has(expr())), + expr().bind("empty-throw"), + anyOf(unless(hasAncestor(cxxCatchStmt())), + hasAncestor(cxxCatchStmt(anyOf( + hasDescendant(functionDecl(HasEmptyThrowExprDescendant)), + hasDescendant(lambdaExpr(HasEmptyThrowExprDescendant))))))), + this); + Finder->addMatcher( + cxxThrowExpr(unless(isExpansionInSystemHeader()), + has(expr(anyOf(RefToExceptionVariable, StdMoveCall, + CopyOrMoveConstruction)))) + .bind("throw"), + this); +} + +void ExceptionRethrowCheck::check(const MatchFinder::MatchResult &Result) { + if (const auto *MatchedThrow = + Result.Nodes.getNodeAs<CXXThrowExpr>("throw")) { + const Expr *ThrownObject = MatchedThrow->getSubExpr(); + diag(MatchedThrow->getThrowLoc(), + "throwing a copy of the caught %0 exception, remove the argument to " + "throw the original exception object") + << ThrownObject->getType().getNonReferenceType(); ---------------- 5chmidti wrote:
This diagnostic could also emit a fix-it that removes the arg, which should always be correct to do. https://github.com/llvm/llvm-project/pull/86448 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
