4 files changed, 43 insertions, 2 deletions
diff --git a/include/clang/AST/RecursiveASTVisitor.h b/include/clang/AST/RecursiveASTVisitor.h
index ac7795f933..acba46dcd7 100644
--- a/include/clang/AST/RecursiveASTVisitor.h
+++ b/include/clang/AST/RecursiveASTVisitor.h
@@ -1776,6 +1776,14 @@ bool RecursiveASTVisitor<Derived>::TraverseFunctionHelper(FunctionDecl *D) {
   // including exception specifications.
   if (TypeSourceInfo *TSI = D->getTypeSourceInfo()) {
     TRY_TO(TraverseTypeLoc(TSI->getTypeLoc()));
+  } else if (getDerived().shouldVisitImplicitCode()) {
+    // Visit parameter variable declarations of the implicit function
+    // if the traverser is visiting implicit code. Parameter variable
+    // declarations do not have valid TypeSourceInfo, so to visit them
+    // we need to traverse the declarations explicitly.
+    for (FunctionDecl::param_const_iterator I = D->param_begin(),
+                                            E = D->param_end(); I != E; ++I)
+      TRY_TO(TraverseDecl(*I));
   }
 
   if (CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(D)) {
diff --git a/unittests/ASTMatchers/ASTMatchersTest.cpp b/unittests/ASTMatchers/ASTMatchersTest.cpp
index 4994192bda..556b0b896e 100644
--- a/unittests/ASTMatchers/ASTMatchersTest.cpp
+++ b/unittests/ASTMatchers/ASTMatchersTest.cpp
@@ -1361,8 +1361,12 @@ TEST(Matcher, References) {
                       ReferenceClassX));
   EXPECT_TRUE(
       matches("class X {}; void y(X y) { const X &x = y; }", ReferenceClassX));
+  // The match here is on the implicit copy constructor code for
+  // class X, not on code 'X x = y'.
   EXPECT_TRUE(
-      notMatches("class X {}; void y(X y) { X x = y; }", ReferenceClassX));
+      matches("class X {}; void y(X y) { X x = y; }", ReferenceClassX));
+  EXPECT_TRUE(
+      notMatches("class X {}; extern X x;", ReferenceClassX));
   EXPECT_TRUE(
       notMatches("class X {}; void y(X *y) { X *&x = y; }", ReferenceClassX));
 }
diff --git a/unittests/Tooling/RecursiveASTVisitorTest.cpp b/unittests/Tooling/RecursiveASTVisitorTest.cpp
index b1d6f4a37c..b3a8915a59 100644
--- a/unittests/Tooling/RecursiveASTVisitorTest.cpp
+++ b/unittests/Tooling/RecursiveASTVisitorTest.cpp
@@ -37,6 +37,17 @@ public:
  }
 };
 
+class ParmVarDeclVisitorForImplicitCode :
+  public ExpectedLocationVisitor<ParmVarDeclVisitorForImplicitCode> {
+public:
+  bool shouldVisitImplicitCode() const { return true; }
+
+  bool VisitParmVarDecl(ParmVarDecl *ParamVar) {
+    Match(ParamVar->getNameAsString(), ParamVar->getLocStart());
+    return true;
+  }
+};
+
 class CXXMemberCallVisitor
   : public ExpectedLocationVisitor<CXXMemberCallVisitor> {
 public:
@@ -144,6 +155,20 @@ public:
   }
 };
 
+// Test RAV visits parameter variable declaration of the implicit
+// copy assignment operator.
+TEST(RecursiveASTVisitor, VisitsParmVarDeclForImplicitCode) {
+  ParmVarDeclVisitorForImplicitCode Visitor;
+  // Match parameter variable name of implicit copy assignment operator.
+  // This parameter name does not have a valid IdentifierInfo, and shares
+  // same SourceLocation with its class declaration, so we match an empty name
+  // with the class' source location.
+  Visitor.ExpectMatch("", 1, 7);
+  EXPECT_TRUE(Visitor.runOver(
+    "class X {};\n"
+    "void foo(X a, X b) {a = b;}"));
+}
+
 TEST(RecursiveASTVisitor, VisitsBaseClassDeclarations) {
   TypeLocVisitor Visitor;
   Visitor.ExpectMatch("class X", 1, 30);
diff --git a/unittests/Tooling/TestVisitor.h b/unittests/Tooling/TestVisitor.h
index 5ee118ebdc..ec751c350e 100644
--- a/unittests/Tooling/TestVisitor.h
+++ b/unittests/Tooling/TestVisitor.h
@@ -31,7 +31,7 @@ namespace clang {
 /// This is a drop-in replacement for RecursiveASTVisitor itself, with the
 /// additional capability of running it over a snippet of code.
 ///
-/// Visits template instantiations (but not implicit code) by default.
+/// Visits template instantiations and implicit code by default.
 template <typename T>
 class TestVisitor : public RecursiveASTVisitor<T> {
 public:
@@ -56,6 +56,10 @@ public:
     return true;
   }
 
+  bool shouldVisitImplicitCode() const {
+    return true;
+  }
+
 protected:
   virtual ASTFrontendAction* CreateTestAction() {
     return new TestAction(this);