[Sema] A tag decl that is marked as invalid and is used in a decl-spec,
should not impede creating a proper TypeLoc info for the decl-spec.

This improves our semantic error recovery.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@152481 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/AST/TypeLoc.h b/include/clang/AST/TypeLoc.h
index 1c75096..aab87be 100644
--- a/include/clang/AST/TypeLoc.h
+++ b/include/clang/AST/TypeLoc.h
@@ -572,8 +572,9 @@
 
   /// \brief True if the tag was defined in this type specifier.
   bool isDefinition() const {
-    return getDecl()->isCompleteDefinition() &&
-         (getNameLoc().isInvalid() || getNameLoc() == getDecl()->getLocation());
+    TagDecl *D = getDecl();
+    return D->isCompleteDefinition() &&
+         (D->getIdentifier() == 0 || D->getLocation() == getNameLoc());
   }
 };
 
diff --git a/lib/Sema/SemaType.cpp b/lib/Sema/SemaType.cpp
index 505cc8f..919faa0 100644
--- a/lib/Sema/SemaType.cpp
+++ b/lib/Sema/SemaType.cpp
@@ -766,9 +766,6 @@
     ElaboratedTypeKeyword Keyword
       = ElaboratedType::getKeywordForTypeSpec(DS.getTypeSpecType());
     Result = S.getElaboratedType(Keyword, DS.getTypeSpecScope(), Result);
-
-    if (D->isInvalidDecl())
-      declarator.setInvalidType(true);
     break;
   }
   case DeclSpec::TST_typename: {
diff --git a/test/Index/index-invalid-code.m b/test/Index/index-invalid-code.m
new file mode 100644
index 0000000..9084533
--- /dev/null
+++ b/test/Index/index-invalid-code.m
@@ -0,0 +1,8 @@
+struct S {
+  int {
+};
+typedef struct S S;
+
+// RUN: c-index-test -index-file %s | FileCheck %s
+// CHECK: [indexDeclaration]: kind: struct | name: S |
+// CHECK-NOT: [indexDeclaration]: kind: struct | name: S |