3 files changed, 26 insertions, 3 deletions
diff --git a/clang/lib/Serialization/ASTWriter.cpp b/clang/lib/Serialization/ASTWriter.cpp
index 2b096fc0957..de270f35015 100644
--- a/clang/lib/Serialization/ASTWriter.cpp
+++ b/clang/lib/Serialization/ASTWriter.cpp
@@ -4055,10 +4055,11 @@ ASTWriter::ASTWriter(llvm::BitstreamWriter &Stream)
       NextCXXBaseSpecifiersID(1), TypeExtQualAbbrev(0),
       TypeFunctionProtoAbbrev(0), DeclParmVarAbbrev(0),
       DeclContextLexicalAbbrev(0), DeclContextVisibleLookupAbbrev(0),
-      UpdateVisibleAbbrev(0), DeclRefExprAbbrev(0), CharacterLiteralAbbrev(0),
-      DeclRecordAbbrev(0), IntegerLiteralAbbrev(0), DeclTypedefAbbrev(0),
+      UpdateVisibleAbbrev(0), DeclRecordAbbrev(0), DeclTypedefAbbrev(0),
       DeclVarAbbrev(0), DeclFieldAbbrev(0), DeclEnumAbbrev(0),
-      DeclObjCIvarAbbrev(0), DeclCXXMethodAbbrev(0) {}
+      DeclObjCIvarAbbrev(0), DeclCXXMethodAbbrev(0), DeclRefExprAbbrev(0),
+      CharacterLiteralAbbrev(0), IntegerLiteralAbbrev(0),
+      ExprImplicitCastAbbrev(0) {}
 
 ASTWriter::~ASTWriter() {
   llvm::DeleteContainerSeconds(FileDeclIDs);
diff --git a/clang/lib/Serialization/ASTWriterDecl.cpp b/clang/lib/Serialization/ASTWriterDecl.cpp
index 1c6983413a3..dca7796c029 100644
--- a/clang/lib/Serialization/ASTWriterDecl.cpp
+++ b/clang/lib/Serialization/ASTWriterDecl.cpp
@@ -1860,6 +1860,24 @@ void ASTWriter::WriteDeclAbbrevs() {
   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // getKind
   CharacterLiteralAbbrev = Stream.EmitAbbrev(Abv);
 
+  // Abbreviation for EXPR_IMPLICIT_CAST
+  Abv = new BitCodeAbbrev();
+  Abv->Add(BitCodeAbbrevOp(serialization::EXPR_IMPLICIT_CAST));
+  // Stmt
+  // Expr
+  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
+  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
+  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
+  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
+  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
+  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
+  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
+  // CastExpr
+  Abv->Add(BitCodeAbbrevOp(0)); // PathSize
+  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 6)); // CastKind
+  // ImplicitCastExpr
+  ExprImplicitCastAbbrev = Stream.EmitAbbrev(Abv);
+
   Abv = new BitCodeAbbrev();
   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CONTEXT_LEXICAL));
   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
diff --git a/clang/lib/Serialization/ASTWriterStmt.cpp b/clang/lib/Serialization/ASTWriterStmt.cpp
index cee94c401c1..462271a0ea7 100644
--- a/clang/lib/Serialization/ASTWriterStmt.cpp
+++ b/clang/lib/Serialization/ASTWriterStmt.cpp
@@ -635,6 +635,10 @@ ASTStmtWriter::VisitBinaryConditionalOperator(BinaryConditionalOperator *E) {
 
 void ASTStmtWriter::VisitImplicitCastExpr(ImplicitCastExpr *E) {
   VisitCastExpr(E);
+
+  if (E->path_size() == 0)
+    AbbrevToUse = Writer.getExprImplicitCastAbbrev();
+
   Code = serialization::EXPR_IMPLICIT_CAST;
 }