2 files changed, 71 insertions, 0 deletions

diff --git a/clang/lib/AST/ODRHash.cpp b/clang/lib/AST/ODRHash.cpp
index 3f66e58eb86..66b9940b8b0 100644
--- a/clang/lib/AST/ODRHash.cpp
+++ b/clang/lib/AST/ODRHash.cpp
@@ -228,6 +228,13 @@ public:
     Hash.AddQualType(T);
   }
 
+  void AddDecl(const Decl *D) {
+    Hash.AddBoolean(D);
+    if (D) {
+      Hash.AddDecl(D);
+    }
+  }
+
   void Visit(const Decl *D) {
     ID.AddInteger(D->getKind());
     Inherited::Visit(D);
@@ -321,6 +328,16 @@ public:
   void VisitTypeAliasDecl(const TypeAliasDecl *D) {
     Inherited::VisitTypeAliasDecl(D);
   }
+
+  void VisitFriendDecl(const FriendDecl *D) {
+    TypeSourceInfo *TSI = D->getFriendType();
+    Hash.AddBoolean(TSI);
+    if (TSI) {
+      AddQualType(TSI->getType());
+    } else {
+      AddDecl(D->getFriendDecl());
+    }
+  }
 };
 
 // Only allow a small portion of Decl's to be processed.  Remove this once
@@ -335,6 +352,7 @@ bool ODRHash::isWhitelistedDecl(const Decl *D, const CXXRecordDecl *Parent) {
     case Decl::AccessSpec:
     case Decl::CXXMethod:
     case Decl::Field:
+    case Decl::Friend:
     case Decl::StaticAssert:
     case Decl::TypeAlias:
     case Decl::Typedef:
diff --git a/clang/lib/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp
index 3aee3c04001..678ecfc9a3d 100644
--- a/clang/lib/Serialization/ASTReader.cpp
+++ b/clang/lib/Serialization/ASTReader.cpp
@@ -9314,6 +9314,7 @@ void ASTReader::diagnoseOdrViolations() {
         TypeAlias,
         TypeDef,
         Var,
+        Friend,
         Other
       } FirstDiffType = Other,
         SecondDiffType = Other;
@@ -9347,6 +9348,8 @@ void ASTReader::diagnoseOdrViolations() {
           return TypeDef;
         case Decl::Var:
           return Var;
+        case Decl::Friend:
+          return Friend;
         }
       };
 
@@ -9463,6 +9466,9 @@ void ASTReader::diagnoseOdrViolations() {
         VarSingleInitializer,
         VarDifferentInitializer,
         VarConstexpr,
+        FriendTypeFunction,
+        FriendType,
+        FriendFunction,
       };
 
       // These lambdas have the common portions of the ODR diagnostics.  This
@@ -9973,6 +9979,53 @@ void ASTReader::diagnoseOdrViolations() {
         }
         break;
       }
+      case Friend: {
+        FriendDecl *FirstFriend = cast<FriendDecl>(FirstDecl);
+        FriendDecl *SecondFriend = cast<FriendDecl>(SecondDecl);
+
+        NamedDecl *FirstND = FirstFriend->getFriendDecl();
+        NamedDecl *SecondND = SecondFriend->getFriendDecl();
+
+        TypeSourceInfo *FirstTSI = FirstFriend->getFriendType();
+        TypeSourceInfo *SecondTSI = SecondFriend->getFriendType();
+
+        if (FirstND && SecondND) {
+          ODRDiagError(FirstFriend->getFriendLoc(),
+                       FirstFriend->getSourceRange(), FriendFunction)
+              << FirstND;
+          ODRDiagNote(SecondFriend->getFriendLoc(),
+                      SecondFriend->getSourceRange(), FriendFunction)
+              << SecondND;
+
+          Diagnosed = true;
+          break;
+        }
+
+        if (FirstTSI && SecondTSI) {
+          QualType FirstFriendType = FirstTSI->getType();
+          QualType SecondFriendType = SecondTSI->getType();
+          assert(ComputeQualTypeODRHash(FirstFriendType) !=
+                 ComputeQualTypeODRHash(SecondFriendType));
+          ODRDiagError(FirstFriend->getFriendLoc(),
+                       FirstFriend->getSourceRange(), FriendType)
+              << FirstFriendType;
+          ODRDiagNote(SecondFriend->getFriendLoc(),
+                      SecondFriend->getSourceRange(), FriendType)
+              << SecondFriendType;
+          Diagnosed = true;
+          break;
+        }
+
+        ODRDiagError(FirstFriend->getFriendLoc(), FirstFriend->getSourceRange(),
+                     FriendTypeFunction)
+            << (FirstTSI == nullptr);
+        ODRDiagNote(SecondFriend->getFriendLoc(),
+                    SecondFriend->getSourceRange(), FriendTypeFunction)
+            << (SecondTSI == nullptr);
+
+        Diagnosed = true;
+        break;
+      }
       }
 
       if (Diagnosed == true)