Revert me: Add minimal contract which reproduces bug

examples/bug/.gitignore

+# Ignore build artifacts from the local tests sub-crate.
+/target/
+
+# Ignore backup files creates by cargo fmt.
+**/*.rs.bk
+
+# Remove Cargo.lock when creating an executable, leave it for libraries
+# More information here http://doc.crates.io/guide.html#cargotoml-vs-cargolock
+Cargo.lock
\ No newline at end of file

examples/bug/Cargo.toml

+[package]
+name = "bug"
+version = "3.0.0-rc2"
+authors = ["Parity Technologies <admin@parity.io>"]
+edition = "2018"
+
+[dependencies]
+ink_primitives = { version = "3.0.0-rc2", path = "../../crates/primitives", default-features = false }
+ink_metadata = { version = "3.0.0-rc2", path = "../../crates/metadata", default-features = false, features = ["derive"], optional = true }
+ink_env = { version = "3.0.0-rc2", path = "../../crates/env", default-features = false }
+ink_storage = { version = "3.0.0-rc2", path = "../../crates/storage", default-features = false }
+ink_lang = { version = "3.0.0-rc2", path = "../../crates/lang", default-features = false }
+
+scale = { package = "parity-scale-codec", version = "1.3", default-features = false, features = ["derive"] }
+scale-info = { version = "0.4", default-features = false, features = ["derive"], optional = true }
+generic-array = "0.14.1"
+
+
+[lib]
+name = "bug"
+path = "lib.rs"
+crate-type = ["cdylib"]
+
+[features]
+default = ["std"]
+std = [
+    "ink_primitives/std",
+    "ink_metadata",
+    "ink_metadata/std",
+    "ink_env/std",
+    "ink_storage/std",
+    "ink_lang/std",
+    "scale/std",
+    "scale-info",
+    "scale-info/std",
+]
+ink-as-dependency = []

examples/bug/lib.rs

+// Copyright 2018-2020 Parity Technologies (UK) Ltd.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#![cfg_attr(not(feature = "std"), no_std)]
+#![allow(clippy::new_without_default)]
+
+use ink_lang as ink;
+
+#[ink::contract]
+mod bug {
+    use ink_storage::Lazy;
+
+    #[ink(storage)]
+    pub struct Bug {
+        opt: Option<u32>,
+        some_val: Lazy<u32>,
+    }
+
+    impl Bug {
+        #[ink(constructor)]
+        pub fn new() -> Self {
+            Self {
+                opt: None,
+                some_val: Lazy::new(27),
+            }
+        }
+
+        #[ink(message)]
+        pub fn bug(&mut self) -> Result<(), ()> {
+            ink_env::debug_println("get some_val");
+            let _ = *self.some_val;
+
+            ink_env::debug_println("set opt");
+            self.opt = Some(13);
+
+            ink_env::debug_println("end");
+            Ok(())
+        }
+    }
+}