Merge pull request #88 from oli-obk/patch-1

don't freeze globals twice

src/interpreter/mod.rs

@@ -383,9 +383,6 @@ fn pop_stack_frame(&mut self) -> EvalResult<'tcx, ()> {
                         }
                     },
                 }
-                if let Value::ByRef(ptr) = global_value.data.expect("global should have been initialized") {
-                    self.memory.freeze(ptr.alloc_id)?;
-                }
                 assert!(global_value.mutable);
                 global_value.mutable = false;
             } else {