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diff --git a/clang-tools-extra/clang-tidy/misc/VirtualNearMissCheck.cpp b/clang-tools-extra/clang-tidy/misc/VirtualNearMissCheck.cpp
new file mode 100644
index 00000000000..def63ce1882
--- /dev/null
+++ b/clang-tools-extra/clang-tidy/misc/VirtualNearMissCheck.cpp
@@ -0,0 +1,266 @@
+//===--- VirtualNearMissCheck.cpp - clang-tidy-----------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "VirtualNearMissCheck.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/CXXInheritance.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/Lex/Lexer.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang {
+namespace tidy {
+namespace misc {
+
+/// Finds out if the given method overrides some method.
+static bool isOverrideMethod(const CXXMethodDecl *MD) {
+  return MD->size_overridden_methods() > 0 || MD->hasAttr<OverrideAttr>();
+}
+
+/// Checks whether the return types are covariant, according to
+/// C++[class.virtual]p7.
+///
+/// Similar with clang::Sema::CheckOverridingFunctionReturnType.
+/// \returns true if the return types of BaseMD and DerivedMD are covariant.
+static bool checkOverridingFunctionReturnType(const ASTContext *Context,
+                                              const CXXMethodDecl *BaseMD,
+                                              const CXXMethodDecl *DerivedMD) {
+  QualType BaseReturnTy =
+      BaseMD->getType()->getAs<FunctionType>()->getReturnType();
+  QualType DerivedReturnTy =
+      DerivedMD->getType()->getAs<FunctionType>()->getReturnType();
+
+  if (DerivedReturnTy->isDependentType() || BaseReturnTy->isDependentType())
+    return false;
+
+  // Check if return types are identical.
+  if (Context->hasSameType(DerivedReturnTy, BaseReturnTy))
+    return true;
+
+  /// Check if the return types are covariant.
+  /// BTy is the class type in return type of BaseMD. For example,
+  ///    B* Base::md()
+  /// While BRD is the declaration of B.
+  QualType BTy, DTy;
+  const CXXRecordDecl *BRD, *DRD;
+
+  // Both types must be pointers or references to classes.
+  if (const auto *DerivedPT = DerivedReturnTy->getAs<PointerType>()) {
+    if (const auto *BasePT = BaseReturnTy->getAs<PointerType>()) {
+      DTy = DerivedPT->getPointeeType();
+      BTy = BasePT->getPointeeType();
+    }
+  } else if (const auto *DerivedRT = DerivedReturnTy->getAs<ReferenceType>()) {
+    if (const auto *BaseRT = BaseReturnTy->getAs<ReferenceType>()) {
+      DTy = DerivedRT->getPointeeType();
+      BTy = BaseRT->getPointeeType();
+    }
+  }
+
+  // The return types aren't either both pointers or references to a class type.
+  if (DTy.isNull())
+    return false;
+
+  DRD = DTy->getAsCXXRecordDecl();
+  BRD = BTy->getAsCXXRecordDecl();
+  if (DRD == nullptr || BRD == nullptr)
+    return false;
+
+  if (DRD == BRD)
+    return true;
+
+  if (!Context->hasSameUnqualifiedType(DTy, BTy)) {
+    // Begin checking whether the conversion from D to B is valid.
+    CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
+                       /*DetectVirtual=*/false);
+
+    // Check whether D is derived from B, and fill in a CXXBasePaths object.
+    if (!DRD->isDerivedFrom(BRD, Paths))
+      return false;
+
+    // Check ambiguity.
+    if (Paths.isAmbiguous(Context->getCanonicalType(BTy).getUnqualifiedType()))
+      return false;
+
+    // Check accessibility.
+    // FIXME: We currently only support checking if B is accessible base class
+    // of D, or D is the same class which DerivedMD is in.
+    bool IsItself = DRD == DerivedMD->getParent();
+    bool HasPublicAccess = false;
+    for (const auto &Path : Paths) {
+      if (Path.Access == AS_public)
+        HasPublicAccess = true;
+    }
+    if (!HasPublicAccess && !IsItself)
+      return false;
+    // End checking conversion from D to B.
+  }
+
+  // Both pointers or references should have the same cv-qualification.
+  if (DerivedReturnTy.getLocalCVRQualifiers() !=
+      BaseReturnTy.getLocalCVRQualifiers())
+    return false;
+
+  // The class type D should have the same cv-qualification as or less
+  // cv-qualification than the class type B.
+  if (DTy.isMoreQualifiedThan(BTy))
+    return false;
+
+  return true;
+}
+
+/// \returns true if the param types are the same.
+static bool checkParamTypes(const CXXMethodDecl *BaseMD,
+                            const CXXMethodDecl *DerivedMD) {
+  unsigned NumParamA = BaseMD->getNumParams();
+  unsigned NumParamB = DerivedMD->getNumParams();
+  if (NumParamA != NumParamB)
+    return false;
+
+  for (unsigned I = 0; I < NumParamA; I++) {
+    if (BaseMD->getParamDecl(I)->getType() !=
+        DerivedMD->getParamDecl(I)->getType())
+      return false;
+  }
+  return true;
+}
+
+/// \returns true if derived method can override base method except for the
+/// name.
+static bool checkOverrideWithoutName(const ASTContext *Context,
+                                     const CXXMethodDecl *BaseMD,
+                                     const CXXMethodDecl *DerivedMD) {
+  if (BaseMD->getTypeQualifiers() != DerivedMD->getTypeQualifiers())
+    return false;
+
+  if (BaseMD->isStatic() != DerivedMD->isStatic())
+    return false;
+
+  if (BaseMD->getAccess() != DerivedMD->getAccess())
+    return false;
+
+  if (BaseMD->getType() == DerivedMD->getType())
+    return true;
+
+  // Now the function types are not identical. Then check if the return types
+  // are covariant and if the param types are the same.
+  if (!checkOverridingFunctionReturnType(Context, BaseMD, DerivedMD))
+    return false;
+  return checkParamTypes(BaseMD, DerivedMD);
+}
+
+/// Check whether BaseMD overrides DerivedMD.
+///
+/// Prerequisite: the class which BaseMD is in should be a base class of that
+/// DerivedMD is in.
+static bool checkOverrideByDerivedMethod(const CXXMethodDecl *BaseMD,
+                                         const CXXMethodDecl *DerivedMD) {
+  if (BaseMD->getNameAsString() != DerivedMD->getNameAsString())
+    return false;
+
+  if (!checkParamTypes(BaseMD, DerivedMD))
+    return false;
+
+  return true;
+}
+
+/// Generate unique ID for given MethodDecl.
+///
+/// The Id is used as key for 'PossibleMap'.
+/// Typical Id: "Base::func void (void)"
+static std::string generateMethodId(const CXXMethodDecl *MD) {
+  return MD->getQualifiedNameAsString() + " " + MD->getType().getAsString();
+}
+
+bool VirtualNearMissCheck::isPossibleToBeOverridden(
+    const CXXMethodDecl *BaseMD) {
+  std::string Id = generateMethodId(BaseMD);
+  auto Iter = PossibleMap.find(Id);
+  if (Iter != PossibleMap.end())
+    return Iter->second;
+
+  bool IsPossible = !BaseMD->isImplicit() && !isa<CXXConstructorDecl>(BaseMD) &&
+                    BaseMD->isVirtual();
+  PossibleMap[Id] = IsPossible;
+  return IsPossible;
+}
+
+bool VirtualNearMissCheck::isOverriddenByDerivedClass(
+    const CXXMethodDecl *BaseMD, const CXXRecordDecl *DerivedRD) {
+  auto Key = std::make_pair(generateMethodId(BaseMD),
+                            DerivedRD->getQualifiedNameAsString());
+  auto Iter = OverriddenMap.find(Key);
+  if (Iter != OverriddenMap.end())
+    return Iter->second;
+
+  bool IsOverridden = false;
+  for (const CXXMethodDecl *DerivedMD : DerivedRD->methods()) {
+    if (!isOverrideMethod(DerivedMD))
+      continue;
+
+    if (checkOverrideByDerivedMethod(BaseMD, DerivedMD)) {
+      IsOverridden = true;
+      break;
+    }
+  }
+  OverriddenMap[Key] = IsOverridden;
+  return IsOverridden;
+}
+
+void VirtualNearMissCheck::registerMatchers(MatchFinder *Finder) {
+  if (!getLangOpts().CPlusPlus)
+    return;
+
+  Finder->addMatcher(cxxMethodDecl(unless(anyOf(isOverride(), isImplicit(),
+                                                cxxConstructorDecl())))
+                         .bind("method"),
+                     this);
+}
+
+void VirtualNearMissCheck::check(const MatchFinder::MatchResult &Result) {
+  const auto *DerivedMD = Result.Nodes.getNodeAs<CXXMethodDecl>("method");
+  assert(DerivedMD != nullptr);
+
+  if (DerivedMD->isStatic())
+    return;
+
+  const ASTContext *Context = Result.Context;
+
+  const auto *DerivedRD = DerivedMD->getParent();
+
+  for (const auto &BaseSpec : DerivedRD->bases()) {
+    if (const auto *BaseRD = BaseSpec.getType()->getAsCXXRecordDecl()) {
+      for (const auto *BaseMD : BaseRD->methods()) {
+        if (!isPossibleToBeOverridden(BaseMD))
+          continue;
+
+        if (isOverriddenByDerivedClass(BaseMD, DerivedRD))
+          continue;
+
+        unsigned EditDistance =
+            BaseMD->getName().edit_distance(DerivedMD->getName());
+        if (EditDistance > 0 && EditDistance <= EditDistanceThreshold) {
+          if (checkOverrideWithoutName(Context, BaseMD, DerivedMD)) {
+            // A "virtual near miss" is found.
+            diag(DerivedMD->getLocStart(),
+                 "method '%0' has a similar name and the same signature as "
+                 "virtual method '%1'; did you mean to override it?")
+                << DerivedMD->getQualifiedNameAsString()
+                << BaseMD->getQualifiedNameAsString();
+          }
+        }
+      }
+    }
+  }
+}
+
+} // namespace misc
+} // namespace tidy
+} // namespace clang