4 files changed, 7 insertions, 1 deletions
diff --git a/clang/lib/AST/ASTImporter.cpp b/clang/lib/AST/ASTImporter.cpp
index d9c0d7b6bed..650bb53236b 100644
--- a/clang/lib/AST/ASTImporter.cpp
+++ b/clang/lib/AST/ASTImporter.cpp
@@ -2176,6 +2176,7 @@ Decl *ASTNodeImporter::VisitParmVarDecl(ParmVarDecl *D) {
                                             Loc, Name.getAsIdentifierInfo(),
                                             T, TInfo, D->getStorageClass(),
                                             /*FIXME: Default argument*/ 0);
+  ToParm->setHasInheritedDefaultArg(D->hasInheritedDefaultArg());
   return Importer.Imported(D, ToParm);
 }
 
diff --git a/clang/lib/Frontend/PCHReaderDecl.cpp b/clang/lib/Frontend/PCHReaderDecl.cpp
index a3f5eac480c..70aa0dd3c9f 100644
--- a/clang/lib/Frontend/PCHReaderDecl.cpp
+++ b/clang/lib/Frontend/PCHReaderDecl.cpp
@@ -411,6 +411,7 @@ void PCHDeclReader::VisitImplicitParamDecl(ImplicitParamDecl *PD) {
 void PCHDeclReader::VisitParmVarDecl(ParmVarDecl *PD) {
   VisitVarDecl(PD);
   PD->setObjCDeclQualifier((Decl::ObjCDeclQualifier)Record[Idx++]);
+  PD->setHasInheritedDefaultArg(Record[Idx++]);
 }
 
 void PCHDeclReader::VisitFileScopeAsmDecl(FileScopeAsmDecl *AD) {
diff --git a/clang/lib/Frontend/PCHWriterDecl.cpp b/clang/lib/Frontend/PCHWriterDecl.cpp
index 0774797463e..d40658c3f9b 100644
--- a/clang/lib/Frontend/PCHWriterDecl.cpp
+++ b/clang/lib/Frontend/PCHWriterDecl.cpp
@@ -398,6 +398,7 @@ void PCHDeclWriter::VisitImplicitParamDecl(ImplicitParamDecl *D) {
 void PCHDeclWriter::VisitParmVarDecl(ParmVarDecl *D) {
   VisitVarDecl(D);
   Record.push_back(D->getObjCDeclQualifier()); // FIXME: stable encoding
+  Record.push_back(D->hasInheritedDefaultArg());
   Code = pch::DECL_PARM_VAR;
 
 
@@ -412,7 +413,8 @@ void PCHDeclWriter::VisitParmVarDecl(ParmVarDecl *D) {
       D->getPCHLevel() == 0 &&
       D->getStorageClass() == 0 &&
       !D->hasCXXDirectInitializer() && // Can params have this ever?
-      D->getObjCDeclQualifier() == 0)
+      D->getObjCDeclQualifier() == 0 &&
+      !D->hasInheritedDefaultArg())
     AbbrevToUse = Writer.getParmVarDeclAbbrev();
 
   // Check things we know are true of *every* PARM_VAR_DECL, which is more than
@@ -496,6 +498,7 @@ void PCHWriter::WriteDeclsBlockAbbrevs() {
   Abv->Add(BitCodeAbbrevOp(0));                       // HasInit
   // ParmVarDecl
   Abv->Add(BitCodeAbbrevOp(0));                       // ObjCDeclQualifier
+  Abv->Add(BitCodeAbbrevOp(0));                       // HasInheritedDefaultArg
 
   ParmVarDeclAbbrev = Stream.EmitAbbrev(Abv);
 }
diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index 830d2e5eef9..7693e144ba2 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -298,6 +298,7 @@ bool Sema::MergeCXXFunctionDecl(FunctionDecl *New, FunctionDecl *Old) {
       Invalid = true;
     } else if (OldParam->hasDefaultArg()) {
       // Merge the old default argument into the new parameter
+      NewParam->setHasInheritedDefaultArg();
       if (OldParam->hasUninstantiatedDefaultArg())
         NewParam->setUninstantiatedDefaultArg(
                                       OldParam->getUninstantiatedDefaultArg());