From b5ae92f2f52df88ae14504d3a3f2bddb479829b6 Mon Sep 17 00:00:00 2001
From: Douglas Gregor <dgregor@apple.com>
Date: Sun, 9 Oct 2011 23:22:49 +0000
Subject: [PATCH] Diagnose attempts to qualify the name of an instance variable
 or property in an Objective-C++ member access expression. Fixes PR9759.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@141522 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/clang/Basic/DiagnosticSemaKinds.td |  4 +++-
 lib/Sema/SemaExprMember.cpp                | 14 ++++++++++++++
 test/SemaObjCXX/propert-dot-error.mm       | 15 +++++++++++++++
 3 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index 15f667f44a..8356340a22 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -3472,7 +3472,9 @@ def error_nosetter_property_assignment : Error<
   "setter method is needed to assign to object using property" " assignment syntax">;
 def error_no_subobject_property_setting : Error<
   "expression is not assignable">;
-
+def err_qualified_objc_access : Error<
+  "%select{property|ivar}0 access cannot be qualified with '%1'">;
+  
 def ext_freestanding_complex : Extension<
   "complex numbers are an extension in a freestanding C99 implementation">;
 
diff --git a/lib/Sema/SemaExprMember.cpp b/lib/Sema/SemaExprMember.cpp
index 1344e247cf..5b37a6f022 100644
--- a/lib/Sema/SemaExprMember.cpp
+++ b/lib/Sema/SemaExprMember.cpp
@@ -1045,6 +1045,13 @@ Sema::LookupMemberExpr(LookupResult &R, ExprResult &BaseExpr,
 
   // Handle ivar access to Objective-C objects.
   if (const ObjCObjectType *OTy = BaseType->getAs<ObjCObjectType>()) {
+    if (!SS.isEmpty()) {
+      Diag(SS.getRange().getBegin(), diag::err_qualified_objc_access)
+        << 1 << SS.getScopeRep()
+        << FixItHint::CreateRemoval(SS.getRange());
+      SS.clear();
+    }
+    
     IdentifierInfo *Member = MemberName.getAsIdentifierInfo();
 
     // There are three cases for the base type:
@@ -1163,6 +1170,13 @@ Sema::LookupMemberExpr(LookupResult &R, ExprResult &BaseExpr,
   // Objective-C property access.
   const ObjCObjectPointerType *OPT;
   if (!IsArrow && (OPT = BaseType->getAs<ObjCObjectPointerType>())) {
+    if (!SS.isEmpty()) {
+      Diag(SS.getRange().getBegin(), diag::err_qualified_objc_access)
+        << 0 << SS.getScopeRep()
+        << FixItHint::CreateRemoval(SS.getRange());
+      SS.clear();
+    }
+
     // This actually uses the base as an r-value.
     BaseExpr = DefaultLvalueConversion(BaseExpr.take());
     if (BaseExpr.isInvalid())
diff --git a/test/SemaObjCXX/propert-dot-error.mm b/test/SemaObjCXX/propert-dot-error.mm
index 7a5feb42e5..b07c7e8cc2 100644
--- a/test/SemaObjCXX/propert-dot-error.mm
+++ b/test/SemaObjCXX/propert-dot-error.mm
@@ -50,3 +50,18 @@ void g(B *b) {
   b->operator+ = 17; // expected-error{{'B' does not have a member named 'operator+'}}
 }
 @end
+
+// PR9759
+class Forward;
+@interface D {
+@public
+  int ivar;
+}
+
+@property int property;
+@end
+
+void testD(D *d) {
+  d.Forward::property = 17; // expected-error{{property access cannot be qualified with 'Forward::'}}
+  d->Forward::ivar = 12; // expected-error{{ivar access cannot be qualified with 'Forward::'}}
+}
-- 
2.40.0