Merge branch 'main' into add-type-base-for-fneg

Author: LiqinWeng

clang-tools-extra/clang-tidy/bugprone/ReturnConstRefFromParameterCheck.cpp

@@ -7,6 +7,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "ReturnConstRefFromParameterCheck.h"
+#include "clang/AST/Expr.h"
 #include "clang/ASTMatchers/ASTMatchFinder.h"
 #include "clang/ASTMatchers/ASTMatchers.h"
 
@@ -15,19 +16,24 @@ using namespace clang::ast_matchers;
 namespace clang::tidy::bugprone {
 
 void ReturnConstRefFromParameterCheck::registerMatchers(MatchFinder *Finder) {
+  const auto DRef = ignoringParens(
+      declRefExpr(
+          to(parmVarDecl(hasType(hasCanonicalType(
+                             qualType(lValueReferenceType(pointee(
+                                          qualType(isConstQualified()))))
+                                 .bind("type"))))
+                 .bind("param")))
+          .bind("dref"));
+  const auto Func =
+      functionDecl(hasReturnTypeLoc(loc(
+                       qualType(hasCanonicalType(equalsBoundNode("type"))))))
+          .bind("func");
+
+  Finder->addMatcher(returnStmt(hasReturnValue(DRef), hasAncestor(Func)), this);
   Finder->addMatcher(
-      returnStmt(
-          hasReturnValue(declRefExpr(
-              to(parmVarDecl(hasType(hasCanonicalType(
-                                 qualType(lValueReferenceType(pointee(
-                                              qualType(isConstQualified()))))
-                                     .bind("type"))))
-                     .bind("param")))),
-          hasAncestor(
-              functionDecl(hasReturnTypeLoc(loc(qualType(
-                               hasCanonicalType(equalsBoundNode("type"))))))
-                  .bind("func")))
-          .bind("ret"),
+      returnStmt(hasReturnValue(ignoringParens(conditionalOperator(
+          eachOf(hasTrueExpression(DRef), hasFalseExpression(DRef)),
+          hasAncestor(Func))))),
       this);
 }
 
@@ -85,8 +91,8 @@ void ReturnConstRefFromParameterCheck::check(
     const MatchFinder::MatchResult &Result) {
   const auto *FD = Result.Nodes.getNodeAs<FunctionDecl>("func");
   const auto *PD = Result.Nodes.getNodeAs<ParmVarDecl>("param");
-  const auto *R = Result.Nodes.getNodeAs<ReturnStmt>("ret");
-  const SourceRange Range = R->getRetValue()->getSourceRange();
+  const auto *DRef = Result.Nodes.getNodeAs<DeclRefExpr>("dref");
+  const SourceRange Range = DRef->getSourceRange();
   if (Range.isInvalid())
     return;
 

clang-tools-extra/clangd/ModulesBuilder.cpp

@@ -12,6 +12,7 @@
 #include "clang/Frontend/FrontendAction.h"
 #include "clang/Frontend/FrontendActions.h"
 #include "clang/Serialization/ASTReader.h"
+#include "clang/Serialization/InMemoryModuleCache.h"
 
 namespace clang {
 namespace clangd {
@@ -127,50 +128,68 @@ struct ModuleFile {
   std::string ModuleFilePath;
 };
 
-bool IsModuleFileUpToDate(
-    PathRef ModuleFilePath,
-    const PrerequisiteModules &RequisiteModules) {
-IntrusiveRefCntPtr<DiagnosticsEngine> Diags =
-      CompilerInstance::createDiagnostics(new DiagnosticOptions());
-
+bool IsModuleFileUpToDate(PathRef ModuleFilePath,
+                          const PrerequisiteModules &RequisiteModules,
+                          llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS) {
   auto HSOpts = std::make_shared<HeaderSearchOptions>();
   RequisiteModules.adjustHeaderSearchOptions(*HSOpts);
   HSOpts->ForceCheckCXX20ModulesInputFiles = true;
   HSOpts->ValidateASTInputFilesContent = true;
 
+  clang::clangd::IgnoreDiagnostics IgnoreDiags;
+  IntrusiveRefCntPtr<DiagnosticsEngine> Diags =
+      CompilerInstance::createDiagnostics(new DiagnosticOptions, &IgnoreDiags,
+                                          /*ShouldOwnClient=*/false);
+
+  LangOptions LangOpts;
+  LangOpts.SkipODRCheckInGMF = true;
+
+  FileManager FileMgr(FileSystemOptions(), VFS);
+
+  SourceManager SourceMgr(*Diags, FileMgr);
+
+  HeaderSearch HeaderInfo(HSOpts, SourceMgr, *Diags, LangOpts,
+                          /*Target=*/nullptr);
+
+  TrivialModuleLoader ModuleLoader;
+  Preprocessor PP(std::make_shared<PreprocessorOptions>(), *Diags, LangOpts,
+                  SourceMgr, HeaderInfo, ModuleLoader);
+
+  IntrusiveRefCntPtr<InMemoryModuleCache> ModuleCache = new InMemoryModuleCache;
   PCHContainerOperations PCHOperations;
-  std::unique_ptr<ASTUnit> Unit = ASTUnit::LoadFromASTFile(
-      ModuleFilePath.str(), PCHOperations.getRawReader(), ASTUnit::LoadASTOnly,
-      Diags, FileSystemOptions(), std::move(HSOpts));
+  ASTReader Reader(PP, *ModuleCache, /*ASTContext=*/nullptr,
+                   PCHOperations.getRawReader(), {});
 
-  if (!Unit)
-    return false;
+  // We don't need any listener here. By default it will use a validator
+  // listener.
+  Reader.setListener(nullptr);
 
-  auto Reader = Unit->getASTReader();
-  if (!Reader)
+  if (Reader.ReadAST(ModuleFilePath, serialization::MK_MainFile,
+                     SourceLocation(),
+                     ASTReader::ARR_None) != ASTReader::Success)
     return false;
 
   bool UpToDate = true;
-  Reader->getModuleManager().visit([&](serialization::ModuleFile &MF) -> bool {
-    Reader->visitInputFiles(
+  Reader.getModuleManager().visit([&](serialization::ModuleFile &MF) -> bool {
+    Reader.visitInputFiles(
         MF, /*IncludeSystem=*/false, /*Complain=*/false,
         [&](const serialization::InputFile &IF, bool isSystem) {
           if (!IF.getFile() || IF.isOutOfDate())
             UpToDate = false;
         });
-
     return !UpToDate;
   });
-
   return UpToDate;
 }
 
 bool IsModuleFilesUpToDate(
     llvm::SmallVector<PathRef> ModuleFilePaths,
-    const PrerequisiteModules &RequisiteModules) {
-  return llvm::all_of(ModuleFilePaths, [&RequisiteModules](auto ModuleFilePath) {
-    return IsModuleFileUpToDate(ModuleFilePath, RequisiteModules);
-  });
+    const PrerequisiteModules &RequisiteModules,
+    llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS) {
+  return llvm::all_of(
+      ModuleFilePaths, [&RequisiteModules, VFS](auto ModuleFilePath) {
+        return IsModuleFileUpToDate(ModuleFilePath, RequisiteModules, VFS);
+      });
 }
 
 // StandalonePrerequisiteModules - stands for PrerequisiteModules for which all
@@ -347,7 +366,7 @@ bool StandalonePrerequisiteModules::canReuse(
   SmallVector<StringRef> BMIPaths;
   for (auto &MF : RequiredModules)
     BMIPaths.push_back(MF.ModuleFilePath);
-  return IsModuleFilesUpToDate(BMIPaths, *this);
+  return IsModuleFilesUpToDate(BMIPaths, *this, VFS);
 }
 
 } // namespace clangd

clang-tools-extra/docs/ReleaseNotes.rst

@@ -163,6 +163,11 @@ Changes in existing checks
   <clang-tidy/checks/bugprone/posix-return>` check to support integer literals
   as LHS and posix call as RHS of comparison.
 
+- Improved :doc:`bugprone-return-const-ref-from-parameter
+  <clang-tidy/checks/bugprone/return-const-ref-from-parameter>` check to
+  diagnose potential dangling references when returning a ``const &`` parameter
+  by using the conditional operator ``cond ? var1 : var2``.
+  
 - Improved :doc:`bugprone-sizeof-expression
   <clang-tidy/checks/bugprone/sizeof-expression>` check to find suspicious
   usages of ``sizeof()``, ``alignof()``, and ``offsetof()`` when adding or

clang-tools-extra/test/clang-tidy/checkers/bugprone/return-const-ref-from-parameter.cpp

@@ -27,6 +27,10 @@ int const &f3(TConstRef a) { return a; }
 int const &f4(TConst &a) { return a; }
 // CHECK-MESSAGES: :[[@LINE-1]]:35: warning: returning a constant reference parameter
 
+int const &f5(TConst &a) { return true ? a : a; }
+// CHECK-MESSAGES: :[[@LINE-1]]:42: warning: returning a constant reference parameter
+// CHECK-MESSAGES: :[[@LINE-2]]:46: warning: returning a constant reference parameter
+
 template <typename T>
 const T& tf1(const T &a) { return a; }
 // CHECK-MESSAGES: :[[@LINE-1]]:35: warning: returning a constant reference parameter
@@ -47,6 +51,11 @@ template <typename T>
 const T& itf4(typename ConstRef<T>::type a) { return a; }
 // CHECK-MESSAGES: :[[@LINE-1]]:54: warning: returning a constant reference parameter
 
+template <typename T>
+const T& itf5(const T &a) { return true ? a : a; }
+// CHECK-MESSAGES: :[[@LINE-1]]:43: warning: returning a constant reference parameter
+// CHECK-MESSAGES: :[[@LINE-2]]:47: warning: returning a constant reference parameter
+
 void instantiate(const int &param, const float &paramf, int &mut_param, float &mut_paramf) {
         itf1(0);
         itf1(param);

clang/docs/ClangFormat.rst

@@ -363,8 +363,3 @@ those as well).
 
 These commands use the file paths shown in the diff output
 so they will only work from the root of the repository.
-
-Current State of Clang Format for LLVM
-======================================
-
-The following table :doc:`ClangFormattedStatus` shows the current status of clang-formatting for the entire LLVM source tree.