don't crash if class is using itself as its super class.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@75178 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 42 insertions, 36 deletions

diff --git a/lib/Sema/SemaDeclObjC.cpp b/lib/Sema/SemaDeclObjC.cpp
index 5cf48d6da0..62d28f326f 100644
--- a/lib/Sema/SemaDeclObjC.cpp
+++ b/lib/Sema/SemaDeclObjC.cpp
@@ -124,48 +124,54 @@ ActOnStartClassInterface(SourceLocation AtInterfaceLoc,
   if (SuperName) {
     // Check if a different kind of symbol declared in this scope.
     PrevDecl = LookupName(TUScope, SuperName, LookupOrdinaryName);
+    if (PrevDecl == IDecl) {
+      Diag(SuperLoc, diag::err_recursive_superclass)
+        << SuperName << ClassName << SourceRange(AtInterfaceLoc, ClassLoc);
+      IDecl->setLocEnd(ClassLoc);
+    }
+    else {
+      ObjCInterfaceDecl *SuperClassDecl = 
+                                dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl);
 
-    ObjCInterfaceDecl *SuperClassDecl = 
-                                  dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl);
-
-    // Diagnose classes that inherit from deprecated classes.
-    if (SuperClassDecl)
-      (void)DiagnoseUseOfDecl(SuperClassDecl, SuperLoc);
+      // Diagnose classes that inherit from deprecated classes.
+      if (SuperClassDecl)
+        (void)DiagnoseUseOfDecl(SuperClassDecl, SuperLoc);
     
-    if (PrevDecl && SuperClassDecl == 0) {
-      // The previous declaration was not a class decl. Check if we have a
-      // typedef. If we do, get the underlying class type.
-      if (const TypedefDecl *TDecl = dyn_cast_or_null<TypedefDecl>(PrevDecl)) {
-        QualType T = TDecl->getUnderlyingType();
-        if (T->isObjCInterfaceType()) {
-          if (NamedDecl *IDecl = T->getAsObjCInterfaceType()->getDecl())
-            SuperClassDecl = dyn_cast<ObjCInterfaceDecl>(IDecl);
+      if (PrevDecl && SuperClassDecl == 0) {
+        // The previous declaration was not a class decl. Check if we have a
+        // typedef. If we do, get the underlying class type.
+        if (const TypedefDecl *TDecl = dyn_cast_or_null<TypedefDecl>(PrevDecl)) {
+          QualType T = TDecl->getUnderlyingType();
+          if (T->isObjCInterfaceType()) {
+            if (NamedDecl *IDecl = T->getAsObjCInterfaceType()->getDecl())
+              SuperClassDecl = dyn_cast<ObjCInterfaceDecl>(IDecl);
+          }
         }
-      }
       
-      // This handles the following case:
-      //
-      // typedef int SuperClass;
-      // @interface MyClass : SuperClass {} @end
-      //
-      if (!SuperClassDecl) {
-        Diag(SuperLoc, diag::err_redefinition_different_kind) << SuperName;
-        Diag(PrevDecl->getLocation(), diag::note_previous_definition);
+        // This handles the following case:
+        //
+        // typedef int SuperClass;
+        // @interface MyClass : SuperClass {} @end
+        //
+        if (!SuperClassDecl) {
+          Diag(SuperLoc, diag::err_redefinition_different_kind) << SuperName;
+          Diag(PrevDecl->getLocation(), diag::note_previous_definition);
+        }
       }
+  
+      if (!dyn_cast_or_null<TypedefDecl>(PrevDecl)) {
+        if (!SuperClassDecl)
+          Diag(SuperLoc, diag::err_undef_superclass)
+            << SuperName << ClassName << SourceRange(AtInterfaceLoc, ClassLoc);
+        else if (SuperClassDecl->isForwardDecl())
+          Diag(SuperLoc, diag::err_undef_superclass)
+            << SuperClassDecl->getDeclName() << ClassName
+            << SourceRange(AtInterfaceLoc, ClassLoc);
+      }
+      IDecl->setSuperClass(SuperClassDecl);
+      IDecl->setSuperClassLoc(SuperLoc);
+      IDecl->setLocEnd(SuperLoc);
     }
-    
-    if (!dyn_cast_or_null<TypedefDecl>(PrevDecl)) {
-      if (!SuperClassDecl)
-        Diag(SuperLoc, diag::err_undef_superclass)
-          << SuperName << ClassName << SourceRange(AtInterfaceLoc, ClassLoc);
-      else if (SuperClassDecl->isForwardDecl())
-        Diag(SuperLoc, diag::err_undef_superclass)
-          << SuperClassDecl->getDeclName() << ClassName
-          << SourceRange(AtInterfaceLoc, ClassLoc);
-    }
-    IDecl->setSuperClass(SuperClassDecl);
-    IDecl->setSuperClassLoc(SuperLoc);
-    IDecl->setLocEnd(SuperLoc);
   } else { // we have a root class.
     IDecl->setLocEnd(ClassLoc);
   }