4 files changed, 118 insertions, 0 deletions

diff --git a/clang/include/clang/AST/ASTImporter.h b/clang/include/clang/AST/ASTImporter.h
index ee48955ca63..e116abaef79 100644
--- a/clang/include/clang/AST/ASTImporter.h
+++ b/clang/include/clang/AST/ASTImporter.h
@@ -23,6 +23,7 @@
 
 namespace clang {
   class ASTContext;
+  class CXXCtorInitializer;
   class Decl;
   class DeclContext;
   class DiagnosticsEngine;
@@ -204,6 +205,14 @@ namespace clang {
     /// \returns the equivalent file ID in the source manager of the "to"
     /// context.
     FileID Import(FileID);
+
+    /// \brief Import the given C++ constructor initializer from the "from"
+    /// context into the "to" context.
+    ///
+    /// \returns the equivalent initializer in the "to" context.
+    CXXCtorInitializer *Import(CXXCtorInitializer *FromInit);
+
+
     
     /// \brief Import the definition of the given declaration, including all of
     /// the declarations it contains.
diff --git a/clang/lib/AST/ASTImporter.cpp b/clang/lib/AST/ASTImporter.cpp
index ec6655391e9..3598dccf0a1 100644
--- a/clang/lib/AST/ASTImporter.cpp
+++ b/clang/lib/AST/ASTImporter.cpp
@@ -3020,6 +3020,22 @@ Decl *ASTNodeImporter::VisitFunctionDecl(FunctionDecl *D) {
                                             D->isInlineSpecified(), 
                                             D->isImplicit(),
                                             D->isConstexpr());
+    if (unsigned NumInitializers = FromConstructor->getNumCtorInitializers()) {
+      SmallVector<CXXCtorInitializer *, 4> CtorInitializers;
+      for (CXXCtorInitializer *I : FromConstructor->inits()) {
+        CXXCtorInitializer *ToI =
+            cast_or_null<CXXCtorInitializer>(Importer.Import(I));
+        if (!ToI && I)
+          return nullptr;
+        CtorInitializers.push_back(ToI);
+      }
+      CXXCtorInitializer **Memory =
+          new (Importer.getToContext()) CXXCtorInitializer *[NumInitializers];
+      std::copy(CtorInitializers.begin(), CtorInitializers.end(), Memory);
+      CXXConstructorDecl *ToCtor = llvm::cast<CXXConstructorDecl>(ToFunction);
+      ToCtor->setCtorInitializers(Memory);
+      ToCtor->setNumCtorInitializers(NumInitializers);
+    }
   } else if (isa<CXXDestructorDecl>(D)) {
     ToFunction = CXXDestructorDecl::Create(Importer.getToContext(),
                                            cast<CXXRecordDecl>(DC),
@@ -6351,6 +6367,72 @@ FileID ASTImporter::Import(FileID FromID) {
   return ToID;
 }
 
+CXXCtorInitializer *ASTImporter::Import(CXXCtorInitializer *From) {
+  Expr *ToExpr = Import(From->getInit());
+  if (!ToExpr && From->getInit())
+    return nullptr;
+
+  if (From->isBaseInitializer()) {
+    TypeSourceInfo *ToTInfo = Import(From->getTypeSourceInfo());
+    if (!ToTInfo && From->getTypeSourceInfo())
+      return nullptr;
+
+    return new (ToContext) CXXCtorInitializer(
+        ToContext, ToTInfo, From->isBaseVirtual(), Import(From->getLParenLoc()),
+        ToExpr, Import(From->getRParenLoc()),
+        From->isPackExpansion() ? Import(From->getEllipsisLoc())
+                                : SourceLocation());
+  } else if (From->isMemberInitializer()) {
+    FieldDecl *ToField =
+        llvm::cast_or_null<FieldDecl>(Import(From->getMember()));
+    if (!ToField && From->getMember())
+      return nullptr;
+
+    return new (ToContext) CXXCtorInitializer(
+        ToContext, ToField, Import(From->getMemberLocation()),
+        Import(From->getLParenLoc()), ToExpr, Import(From->getRParenLoc()));
+  } else if (From->isIndirectMemberInitializer()) {
+    IndirectFieldDecl *ToIField = llvm::cast_or_null<IndirectFieldDecl>(
+        Import(From->getIndirectMember()));
+    if (!ToIField && From->getIndirectMember())
+      return nullptr;
+
+    return new (ToContext) CXXCtorInitializer(
+        ToContext, ToIField, Import(From->getMemberLocation()),
+        Import(From->getLParenLoc()), ToExpr, Import(From->getRParenLoc()));
+  } else if (From->isDelegatingInitializer()) {
+    TypeSourceInfo *ToTInfo = Import(From->getTypeSourceInfo());
+    if (!ToTInfo && From->getTypeSourceInfo())
+      return nullptr;
+
+    return new (ToContext)
+        CXXCtorInitializer(ToContext, ToTInfo, Import(From->getLParenLoc()),
+                           ToExpr, Import(From->getRParenLoc()));
+  } else if (unsigned NumArrayIndices = From->getNumArrayIndices()) {
+    FieldDecl *ToField =
+        llvm::cast_or_null<FieldDecl>(Import(From->getMember()));
+    if (!ToField && From->getMember())
+      return nullptr;
+
+    SmallVector<VarDecl *, 4> ToAIs(NumArrayIndices);
+
+    for (unsigned AII = 0; AII < NumArrayIndices; ++AII) {
+      VarDecl *ToArrayIndex =
+          dyn_cast_or_null<VarDecl>(Import(From->getArrayIndex(AII)));
+      if (!ToArrayIndex && From->getArrayIndex(AII))
+        return nullptr;
+    }
+
+    return CXXCtorInitializer::Create(
+        ToContext, ToField, Import(From->getMemberLocation()),
+        Import(From->getLParenLoc()), ToExpr, Import(From->getRParenLoc()),
+        ToAIs.data(), NumArrayIndices);
+  } else {
+    return nullptr;
+  }
+}
+
+
 void ASTImporter::ImportDefinition(Decl *From) {
   Decl *To = Import(From);
   if (!To)
diff --git a/clang/test/ASTMerge/Inputs/init-ctors-classes.cpp b/clang/test/ASTMerge/Inputs/init-ctors-classes.cpp
new file mode 100644
index 00000000000..616e5dfebcc
--- /dev/null
+++ b/clang/test/ASTMerge/Inputs/init-ctors-classes.cpp
@@ -0,0 +1,17 @@
+class A_base
+{
+public:
+  int x;
+  A_base(int _x) : x(_x) {
+  }
+};
+
+class A : public A_base
+{
+public:
+  int y;
+  struct { int z; };
+  int array[2];
+  A(int _x) : A_base(_x), y(0), z(1), array{{2},{3}} {
+  }
+};
diff --git a/clang/test/ASTMerge/init-ctors.cpp b/clang/test/ASTMerge/init-ctors.cpp
new file mode 100644
index 00000000000..5f0ba4decd9
--- /dev/null
+++ b/clang/test/ASTMerge/init-ctors.cpp
@@ -0,0 +1,10 @@
+// RUN: %clang_cc1 -triple %itanium_abi_triple -std=c++1z -emit-pch -o %t.1.ast %S/Inputs/init-ctors-classes.cpp
+// RUN: %clang_cc1 -triple %itanium_abi_triple -std=c++1z -ast-merge %t.1.ast -fsyntax-only -verify %s
+// expected-no-diagnostics
+
+class B {
+  int method_1() {
+    A a(0);
+    return a.x;
+  }
+};