Index: include/clang/Basic/DiagnosticASTKinds.td
===================================================================
--- include/clang/Basic/DiagnosticASTKinds.td
+++ include/clang/Basic/DiagnosticASTKinds.td
@@ -206,7 +206,9 @@
 def note_odr_tag_kind_here: Note<
   "%0 is a %select{struct|interface|union|class|enum}1 here">;
 def note_odr_field : Note<"field %0 has type %1 here">;
+def note_odr_friend : Note<"friend declared here">;
 def note_odr_missing_field : Note<"no corresponding field here">;
+def note_odr_missing_friend : Note<"no corresponding friend here">;
 def note_odr_bit_field : Note<"bit-field %0 with type %1 and length %2 here">;
 def note_odr_not_bit_field : Note<"field %0 is not a bit-field">;
 def note_odr_base : Note<"class has base type %0">;
Index: lib/AST/ASTImporter.cpp
===================================================================
--- lib/AST/ASTImporter.cpp
+++ lib/AST/ASTImporter.cpp
@@ -2214,8 +2214,12 @@
 
   // Not found. Create it.
   FriendDecl::FriendUnion ToFU;
-  if (NamedDecl *FriendD = D->getFriendDecl())
-    ToFU = cast_or_null<NamedDecl>(Importer.Import(FriendD));
+  if (NamedDecl *FriendD = D->getFriendDecl()) {
+    auto ToFriendD = cast_or_null<NamedDecl>(Importer.Import(FriendD));
+    if (ToFriendD && FriendD->getFriendObjectKind())
+      ToFriendD->setObjectOfFriendDecl();
+     ToFU = ToFriendD;
+  }
   else
     ToFU = Importer.Import(D->getFriendType());
   if (!ToFU)
@@ -2237,7 +2241,6 @@
                                        ToTPLists);
 
   Importer.Imported(D, FrD);
-  RD->pushFriendDecl(FrD);
 
   FrD->setAccess(D->getAccess());
   FrD->setLexicalDeclContext(LexicalDC);
Index: lib/AST/ASTStructuralEquivalence.cpp
===================================================================
--- lib/AST/ASTStructuralEquivalence.cpp
+++ lib/AST/ASTStructuralEquivalence.cpp
@@ -900,6 +900,37 @@
           return false;
         }
       }
+
+      // Check the friends for consistency.
+      CXXRecordDecl::friend_iterator Friend2 = D2CXX->friend_begin(),
+              Friend2End = D2CXX->friend_end();
+      for (CXXRecordDecl::friend_iterator Friend1 = D1CXX->friend_begin(),
+                   Friend1End = D1CXX->friend_end();
+           Friend1 != Friend1End; ++Friend1, ++Friend2) {
+        if (Friend2 == Friend2End) {
+          if (Context.Complain) {
+            Context.Diag2(D2->getLocation(),
+                          diag::warn_odr_tag_type_inconsistent)
+                    << Context.ToCtx.getTypeDeclType(D2CXX);
+            Context.Diag1((*Friend1)->getFriendLoc(), diag::note_odr_friend);
+            Context.Diag2(D2->getLocation(), diag::note_odr_missing_friend);
+          }
+          return false;
+        }
+
+        if (!IsStructurallyEquivalent(Context, *Friend1, *Friend2))
+          return false;
+      }
+
+      if (Friend2 != Friend2End) {
+        if (Context.Complain) {
+          Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
+                  << Context.ToCtx.getTypeDeclType(D2);
+          Context.Diag2((*Friend2)->getFriendLoc(), diag::note_odr_friend);
+          Context.Diag1(D1->getLocation(), diag::note_odr_missing_friend);
+        }
+        return false;
+      }
     } else if (D1CXX->getNumBases() > 0) {
       if (Context.Complain) {
         Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
@@ -1107,6 +1138,30 @@
                                           D2->getTemplatedDecl());
 }
 
+static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
+                                     FriendDecl *D1, FriendDecl *D2) {
+  if (D1->getFriendType() && D2->getFriendType()) {
+    if (!::IsStructurallyEquivalent(Context,
+                                    D1->getFriendType()->getType(),
+                                    D2->getFriendType()->getType()))
+      return false;
+  } else if (D1->getFriendDecl() && D2->getFriendDecl()) {
+    if (!::IsStructurallyEquivalent(Context, D1->getFriendDecl(),
+                                    D2->getFriendDecl()))
+      return false;
+  }
+
+  return true;
+}
+
+static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
+                                     FunctionDecl *D1, FunctionDecl *D2) {
+  if (!::IsStructurallyEquivalent(Context, D1->getType(), D2->getType()))
+    return false;
+
+  return true;
+}
+
 /// Determine structural equivalence of two declarations.
 static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
                                      Decl *D1, Decl *D2) {
@@ -1301,6 +1356,27 @@
         // Kind mismatch.
         Equivalent = false;
       }
+    } else if (FunctionDecl *FD1 = dyn_cast<FunctionDecl>(D1)) {
+      if (FunctionDecl *FD2 = dyn_cast<FunctionDecl>(D2)) {
+        if (!::IsStructurallyEquivalent(FD1->getIdentifier(),
+                                        FD2->getIdentifier()))
+          Equivalent = false;
+        if (!::IsStructurallyEquivalent(*this, FD1, FD2))
+          Equivalent = false;
+      } else {
+        // Kind mismatch.
+        Equivalent = false;
+      }
+    } else if (FriendDecl *FrD1 = dyn_cast<FriendDecl>(D1)) {
+      if (FriendDecl *FrD2 = dyn_cast<FriendDecl>(D2)) {
+        if (FrD1->getFriendType() && FrD2->getFriendType()) {
+          if (!::IsStructurallyEquivalent(*this, FrD1, FrD2))
+            Equivalent = false;
+        } else {
+          // Kind mismatch.
+          Equivalent = false;
+        }
+      }
     }
 
     if (!Equivalent) {
Index: test/ASTMerge/class/Inputs/class1.cpp
===================================================================
--- test/ASTMerge/class/Inputs/class1.cpp
+++ test/ASTMerge/class/Inputs/class1.cpp
@@ -18,3 +18,31 @@
 enum E {
   b = 1
 };
+
+//Friend import tests
+void f();
+int g(int a);
+struct X;
+struct Y;
+
+struct F1 {
+public:
+  int x;
+  friend struct X;
+  friend int g(int);
+  friend void f();
+};
+
+struct F2 {
+public:
+  int x;
+  friend struct X;
+  friend void f();
+};
+
+struct F3 {
+public:
+  int x;
+  friend int g(int);
+  friend void f();
+};
Index: test/ASTMerge/class/Inputs/class2.cpp
===================================================================
--- test/ASTMerge/class/Inputs/class2.cpp
+++ test/ASTMerge/class/Inputs/class2.cpp
@@ -12,3 +12,29 @@
   a = 0,
   b = 1
 };
+
+//Friend import tests
+void f();
+int g(int a);
+struct X;
+struct Y;
+
+struct F1 {
+public:
+  int x;
+  friend struct X;
+  friend int g(int);
+  friend void f();
+};
+
+struct F2 {
+public:
+  int x;
+  friend struct X;
+};
+
+struct F3 {
+public:
+  int x;
+  friend void f();
+};
Index: test/ASTMerge/class/test.cpp
===================================================================
--- test/ASTMerge/class/test.cpp
+++ test/ASTMerge/class/test.cpp
@@ -12,3 +12,13 @@
 // CHECK: class1.cpp:18:6: warning: type 'E' has incompatible definitions in different translation units
 // CHECK: class1.cpp:19:3: note: enumerator 'b' with value 1 here
 // CHECK: class2.cpp:12:3: note: enumerator 'a' with value 0 here
+
+// CHECK: class1.cpp:36:8: warning: type 'F2' has incompatible definitions in different translation units
+// CHECK: class1.cpp:39:3: note: friend declared here
+// CHECK: class2.cpp:30:8: note: no corresponding friend here
+
+// CHECK: class1.cpp:43:8: warning: type 'F3' has incompatible definitions in different translation units
+// CHECK: class1.cpp:46:3: note: friend declared here
+// CHECK: class2.cpp:36:8: note: no corresponding friend here
+
+// CHECK: 4 warnings generated.