Attempt workaround for possible bug in Apple's LLVM g++ 4.2.1

ucbhelper/source/provider/contenthelper.cxx

@@ -795,7 +795,18 @@ uno::Reference< uno::XInterface > SAL_CALL ContentImplHelper::getParent()
         }
     }
 
+#if defined(__llvm__) && __GNUC__ == 4 && __GNUC_MINOR__ == 2
+    // No idea if this works... but it compiles, links, and just
+    // "return xParent" causes an undefined symbol:
+
+    // uno::Reference<uno::XInterface>::operator uno::Reference<uno::XInterface> const&() const
+
+    // (com::sun::star:: omitted for brevity)
+
+    return uno::Reference< uno::XInterface >(xParent);
+#else
     return xParent;
+#endif
 }
 
 //=========================================================================