Fix <rdar://problem/5987482> clang on xcode: null dereference in Sema::ActOnMemberReferenceExpr.

In addition to fixing the crasher, this commit fixes further improves property lookup (by searching protocols of qualified interfaces..."NSObject <prot>").

llvm-svn: 52001

1 files changed, 22 insertions, 0 deletions

diff --git a/clang/lib/AST/DeclObjC.cpp b/clang/lib/AST/DeclObjC.cpp
index e493d27ac33..6536df6e1e1 100644
--- a/clang/lib/AST/DeclObjC.cpp
+++ b/clang/lib/AST/DeclObjC.cpp
@@ -157,6 +157,14 @@ ObjCPropertyDecl *
     if (property)
       return property;
   }
+  // Look through protocols.
+  for (ObjCInterfaceDecl::protocol_iterator I = protocol_begin(),
+       E = protocol_end(); I != E; ++I) {
+    ObjCProtocolDecl *Protocol = *I;
+    ObjCPropertyDecl *property = Protocol->FindPropertyDeclaration(PropertyId);
+    if (property)
+      return property;
+  }
   if (getSuperClass())
     return getSuperClass()->FindPropertyDeclaration(PropertyId);
   return 0;
@@ -397,6 +405,20 @@ ObjCCategoryDecl::FindPropertyDeclaration(IdentifierInfo *PropertyId) const {
   return 0;
 }
 
+/// FindPropertyDeclaration - Finds declaration of the property given its name
+/// in 'PropertyId' and returns it. It returns 0, if not found.
+///
+ObjCPropertyDecl *
+ObjCProtocolDecl::FindPropertyDeclaration(IdentifierInfo *PropertyId) const {
+  for (ObjCProtocolDecl::classprop_iterator I = classprop_begin(),
+       E = classprop_end(); I != E; ++I) {
+    ObjCPropertyDecl *property = *I;
+    if (property->getIdentifier() == PropertyId)
+      return property;
+  }
+  return 0;
+}
+
 ObjCIvarDecl *ObjCInterfaceDecl::lookupInstanceVariable(
   IdentifierInfo *ID, ObjCInterfaceDecl *&clsDeclared) {
   ObjCInterfaceDecl* ClassDecl = this;