1 //===--- MustCheckErrsCheck.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 "MustCheckErrsCheck.h" 10 #include "clang/AST/ASTContext.h" 11 #include "clang/ASTMatchers/ASTMatchFinder.h" 12 13 using namespace clang::ast_matchers; 14 15 namespace clang { 16 namespace tidy { 17 namespace linuxkernel { 18 19 void MustCheckErrsCheck::registerMatchers(MatchFinder *Finder) { 20 auto ErrFn = 21 functionDecl(hasAnyName("ERR_PTR", "PTR_ERR", "IS_ERR", "IS_ERR_OR_NULL", 22 "ERR_CAST", "PTR_ERR_OR_ZERO")); 23 auto NonCheckingStmts = stmt(anyOf(compoundStmt(), labelStmt())); 24 Finder->addMatcher( 25 callExpr(callee(ErrFn), hasParent(NonCheckingStmts)).bind("call"), 26 this); 27 28 auto ReturnToCheck = returnStmt(hasReturnValue(callExpr(callee(ErrFn)))); 29 auto ReturnsErrFn = functionDecl(hasDescendant(ReturnToCheck)); 30 Finder->addMatcher(callExpr(callee(ReturnsErrFn), hasParent(NonCheckingStmts)) 31 .bind("transitive_call"), 32 this); 33 } 34 35 void MustCheckErrsCheck::check(const MatchFinder::MatchResult &Result) { 36 const CallExpr *MatchedCallExpr = Result.Nodes.getNodeAs<CallExpr>("call"); 37 if (MatchedCallExpr) { 38 diag(MatchedCallExpr->getExprLoc(), "result from function %0 is unused") 39 << MatchedCallExpr->getDirectCallee(); 40 } 41 42 const CallExpr *MatchedTransitiveCallExpr = 43 Result.Nodes.getNodeAs<CallExpr>("transitive_call"); 44 if (MatchedTransitiveCallExpr) { 45 diag(MatchedTransitiveCallExpr->getExprLoc(), 46 "result from function %0 is unused but represents an error value") 47 << MatchedTransitiveCallExpr->getDirectCallee(); 48 } 49 } 50 51 } // namespace linuxkernel 52 } // namespace tidy 53 } // namespace clang 54