1 //===--- AvoidCapturingLambdaCoroutinesCheck.cpp - clang-tidy -------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "AvoidCapturingLambdaCoroutinesCheck.h"
10 #include "clang/AST/ASTContext.h"
11 #include "clang/ASTMatchers/ASTMatchFinder.h"
12 
13 using namespace clang::ast_matchers;
14 
15 namespace clang::tidy::cppcoreguidelines {
16 
17 namespace {
AST_MATCHER(LambdaExpr,hasCoroutineBody)18 AST_MATCHER(LambdaExpr, hasCoroutineBody) {
19   const Stmt *Body = Node.getBody();
20   return Body != nullptr && CoroutineBodyStmt::classof(Body);
21 }
22 
AST_MATCHER(LambdaExpr,hasCaptures)23 AST_MATCHER(LambdaExpr, hasCaptures) { return Node.capture_size() != 0U; }
24 } // namespace
25 
registerMatchers(MatchFinder * Finder)26 void AvoidCapturingLambdaCoroutinesCheck::registerMatchers(
27     MatchFinder *Finder) {
28   Finder->addMatcher(
29       lambdaExpr(hasCaptures(), hasCoroutineBody()).bind("lambda"), this);
30 }
31 
isLanguageVersionSupported(const LangOptions & LangOpts) const32 bool AvoidCapturingLambdaCoroutinesCheck::isLanguageVersionSupported(
33     const LangOptions &LangOpts) const {
34   return LangOpts.CPlusPlus20;
35 }
36 
check(const MatchFinder::MatchResult & Result)37 void AvoidCapturingLambdaCoroutinesCheck::check(
38     const MatchFinder::MatchResult &Result) {
39   const auto *MatchedLambda = Result.Nodes.getNodeAs<LambdaExpr>("lambda");
40   diag(MatchedLambda->getExprLoc(),
41        "coroutine lambda may cause use-after-free, avoid captures or ensure "
42        "lambda closure object has guaranteed lifetime");
43 }
44 
45 } // namespace clang::tidy::cppcoreguidelines
46