The AST importer had a bug where it would enter into an infinite recursion

when importing type parameter lists.  The reason is that type parameters
have their DeclContexts set to the interface that is parameterized with those
types, and the importer would follow that loop and blow the stack out.

I've changed the way this works so that the type parameters are only imported
after the interface that contains them has been registered via the Imported()
function.

This is tested by LLDB.

<rdar://problem/20315663>

llvm-svn: 241556

1 files changed, 22 insertions, 13 deletions

diff --git a/clang/lib/AST/DeclObjC.cpp b/clang/lib/AST/DeclObjC.cpp
index da4bc549cf4..b540e37cd07 100644
--- a/clang/lib/AST/DeclObjC.cpp
+++ b/clang/lib/AST/DeclObjC.cpp
@@ -259,6 +259,15 @@ ObjCTypeParamList *ObjCInterfaceDecl::getTypeParamList() const {
   return nullptr;
 }
 
+void ObjCInterfaceDecl::setTypeParamList(ObjCTypeParamList *TPL) {
+  TypeParamList = TPL;
+  if (!TPL)
+    return;
+  // Set the declaration context of each of the type parameters.
+  for (auto typeParam : *TypeParamList)
+    typeParam->setDeclContext(this);
+}
+
 ObjCInterfaceDecl *ObjCInterfaceDecl::getSuperClass() const {
   // FIXME: Should make sure no callers ever do this.
   if (!hasDefinition())
@@ -1302,7 +1311,7 @@ ObjCInterfaceDecl::ObjCInterfaceDecl(const ASTContext &C, DeclContext *DC,
                                      ObjCInterfaceDecl *PrevDecl,
                                      bool IsInternal)
     : ObjCContainerDecl(ObjCInterface, DC, Id, CLoc, AtLoc),
-      redeclarable_base(C), TypeForDecl(nullptr), TypeParamList(typeParamList),
+      redeclarable_base(C), TypeForDecl(nullptr), TypeParamList(nullptr),
       Data() {
   setPreviousDecl(PrevDecl);
   
@@ -1312,11 +1321,7 @@ ObjCInterfaceDecl::ObjCInterfaceDecl(const ASTContext &C, DeclContext *DC,
   
   setImplicit(IsInternal);
 
-  // Update the declaration context of the type parameters.
-  if (typeParamList) {
-    for (auto typeParam : *typeParamList)
-      typeParam->setDeclContext(this);
-  }
+  setTypeParamList(typeParamList);
 }
 
 void ObjCInterfaceDecl::LoadExternalDefinition() const {
@@ -1799,16 +1804,11 @@ ObjCCategoryDecl::ObjCCategoryDecl(DeclContext *DC, SourceLocation AtLoc,
                                    SourceLocation IvarLBraceLoc,
                                    SourceLocation IvarRBraceLoc)
   : ObjCContainerDecl(ObjCCategory, DC, Id, ClassNameLoc, AtLoc),
-    ClassInterface(IDecl), TypeParamList(typeParamList),
+    ClassInterface(IDecl), TypeParamList(nullptr),
     NextClassCategory(nullptr), CategoryNameLoc(CategoryNameLoc),
     IvarLBraceLoc(IvarLBraceLoc), IvarRBraceLoc(IvarRBraceLoc) 
 {
-  // Set the declaration context of each of the type parameters.
-  if (typeParamList) {
-    for (auto typeParam : *typeParamList) {
-      typeParam->setDeclContext(this);
-    }
-  }
+  setTypeParamList(typeParamList);
 }
 
 ObjCCategoryDecl *ObjCCategoryDecl::Create(ASTContext &C, DeclContext *DC,
@@ -1853,6 +1853,15 @@ void ObjCCategoryDecl::setImplementation(ObjCCategoryImplDecl *ImplD) {
   getASTContext().setObjCImplementation(this, ImplD);
 }
 
+void ObjCCategoryDecl::setTypeParamList(ObjCTypeParamList *TPL) {
+  TypeParamList = TPL;
+  if (!TPL)
+    return;
+  // Set the declaration context of each of the type parameters.
+  for (auto typeParam : *TypeParamList)
+    typeParam->setDeclContext(this);
+}
+
 
 //===----------------------------------------------------------------------===//
 // ObjCCategoryImplDecl