| //===--- UnusedReturnValueCheck.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 "UnusedReturnValueCheck.h" |
| #include "../utils/OptionsUtils.h" |
| #include "clang/AST/ASTContext.h" |
| #include "clang/ASTMatchers/ASTMatchFinder.h" |
| |
| using namespace clang::ast_matchers; |
| using namespace clang::ast_matchers::internal; |
| |
| namespace clang { |
| namespace tidy { |
| namespace bugprone { |
| |
| namespace { |
| |
| // Matches functions that are instantiated from a class template member function |
| // matching InnerMatcher. Functions not instantiated from a class template |
| // member function are matched directly with InnerMatcher. |
| AST_MATCHER_P(FunctionDecl, isInstantiatedFrom, Matcher<FunctionDecl>, |
| InnerMatcher) { |
| FunctionDecl *InstantiatedFrom = Node.getInstantiatedFromMemberFunction(); |
| return InnerMatcher.matches(InstantiatedFrom ? *InstantiatedFrom : Node, |
| Finder, Builder); |
| } |
| |
| } // namespace |
| |
| UnusedReturnValueCheck::UnusedReturnValueCheck(llvm::StringRef Name, |
| ClangTidyContext *Context) |
| : ClangTidyCheck(Name, Context), |
| CheckedFunctions(Options.get("CheckedFunctions", |
| "::std::async;" |
| "::std::launder;" |
| "::std::remove;" |
| "::std::remove_if;" |
| "::std::unique;" |
| "::std::unique_ptr::release;" |
| "::std::basic_string::empty;" |
| "::std::vector::empty;" |
| "::std::back_inserter;" |
| "::std::distance;" |
| "::std::find;" |
| "::std::find_if;" |
| "::std::inserter;" |
| "::std::lower_bound;" |
| "::std::make_pair;" |
| "::std::map::count;" |
| "::std::map::find;" |
| "::std::map::lower_bound;" |
| "::std::multimap::equal_range;" |
| "::std::multimap::upper_bound;" |
| "::std::set::count;" |
| "::std::set::find;" |
| "::std::setfill;" |
| "::std::setprecision;" |
| "::std::setw;" |
| "::std::upper_bound;" |
| "::std::vector::at;" |
| // C standard library |
| "::bsearch;" |
| "::ferror;" |
| "::feof;" |
| "::isalnum;" |
| "::isalpha;" |
| "::isblank;" |
| "::iscntrl;" |
| "::isdigit;" |
| "::isgraph;" |
| "::islower;" |
| "::isprint;" |
| "::ispunct;" |
| "::isspace;" |
| "::isupper;" |
| "::iswalnum;" |
| "::iswprint;" |
| "::iswspace;" |
| "::isxdigit;" |
| "::memchr;" |
| "::memcmp;" |
| "::strcmp;" |
| "::strcoll;" |
| "::strncmp;" |
| "::strpbrk;" |
| "::strrchr;" |
| "::strspn;" |
| "::strstr;" |
| "::wcscmp;" |
| // POSIX |
| "::access;" |
| "::bind;" |
| "::connect;" |
| "::difftime;" |
| "::dlsym;" |
| "::fnmatch;" |
| "::getaddrinfo;" |
| "::getopt;" |
| "::htonl;" |
| "::htons;" |
| "::iconv_open;" |
| "::inet_addr;" |
| "::isascii;" |
| "::isatty;" |
| "::mmap;" |
| "::newlocale;" |
| "::openat;" |
| "::pathconf;" |
| "::pthread_equal;" |
| "::pthread_getspecific;" |
| "::pthread_mutex_trylock;" |
| "::readdir;" |
| "::readlink;" |
| "::recvmsg;" |
| "::regexec;" |
| "::scandir;" |
| "::semget;" |
| "::setjmp;" |
| "::shm_open;" |
| "::shmget;" |
| "::sigismember;" |
| "::strcasecmp;" |
| "::strsignal;" |
| "::ttyname")) {} |
| |
| void UnusedReturnValueCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) { |
| Options.store(Opts, "CheckedFunctions", CheckedFunctions); |
| } |
| |
| void UnusedReturnValueCheck::registerMatchers(MatchFinder *Finder) { |
| auto FunVec = utils::options::parseStringList(CheckedFunctions); |
| auto MatchedCallExpr = expr(ignoringImplicit(ignoringParenImpCasts( |
| callExpr(callee(functionDecl( |
| // Don't match void overloads of checked functions. |
| unless(returns(voidType())), |
| isInstantiatedFrom(hasAnyName( |
| std::vector<StringRef>(FunVec.begin(), FunVec.end())))))) |
| .bind("match")))); |
| |
| auto UnusedInCompoundStmt = |
| compoundStmt(forEach(MatchedCallExpr), |
| // The checker can't currently differentiate between the |
| // return statement and other statements inside GNU statement |
| // expressions, so disable the checker inside them to avoid |
| // false positives. |
| unless(hasParent(stmtExpr()))); |
| auto UnusedInIfStmt = |
| ifStmt(eachOf(hasThen(MatchedCallExpr), hasElse(MatchedCallExpr))); |
| auto UnusedInWhileStmt = whileStmt(hasBody(MatchedCallExpr)); |
| auto UnusedInDoStmt = doStmt(hasBody(MatchedCallExpr)); |
| auto UnusedInForStmt = |
| forStmt(eachOf(hasLoopInit(MatchedCallExpr), |
| hasIncrement(MatchedCallExpr), hasBody(MatchedCallExpr))); |
| auto UnusedInRangeForStmt = cxxForRangeStmt(hasBody(MatchedCallExpr)); |
| auto UnusedInCaseStmt = switchCase(forEach(MatchedCallExpr)); |
| |
| Finder->addMatcher( |
| stmt(anyOf(UnusedInCompoundStmt, UnusedInIfStmt, UnusedInWhileStmt, |
| UnusedInDoStmt, UnusedInForStmt, UnusedInRangeForStmt, |
| UnusedInCaseStmt)), |
| this); |
| } |
| |
| void UnusedReturnValueCheck::check(const MatchFinder::MatchResult &Result) { |
| if (const auto *Matched = Result.Nodes.getNodeAs<CallExpr>("match")) { |
| diag(Matched->getBeginLoc(), |
| "the value returned by this function should be used") |
| << Matched->getSourceRange(); |
| diag(Matched->getBeginLoc(), |
| "cast the expression to void to silence this warning", |
| DiagnosticIDs::Note); |
| } |
| } |
| |
| } // namespace bugprone |
| } // namespace tidy |
| } // namespace clang |
