diff --git a/compiler/cpp/src/generate/t_cocoa_generator.cc b/compiler/cpp/src/generate/t_cocoa_generator.cc
index 9ade7fd..fc85365 100644
--- a/compiler/cpp/src/generate/t_cocoa_generator.cc
+++ b/compiler/cpp/src/generate/t_cocoa_generator.cc
@@ -486,7 +486,7 @@
         // is now retaining it
         if (type_can_be_null((*f_iter)->get_type())) {
           // deserialized strings are autorelease, so don't release them
-          if (!((*f_iter)->get_type()->is_string())) {
+          if (!(get_true_type((*f_iter)->get_type())->is_string())) {
             indent(out) << "[fieldValue release];" << endl;
           }
         }