Refactor (#285)

examples/free_by_gc/Cargo.toml

@@ -2,7 +2,7 @@
 name = "free_by_gc"
 version = "0.1.0"
 authors = ["Yota Toyama <raviqqe@gmail.com>"]
-edition = "2018"
+edition = "2021"
 publish = false
 
 [dependencies]

examples/free_by_gc/src/main.rs

@@ -1,5 +1,3 @@
-extern crate bdwgc_alloc;
-
 use bdwgc_alloc::Allocator;
 use std::alloc::Layout;
 
@@ -10,6 +8,6 @@ fn main() {
     unsafe { Allocator::initialize() }
 
     loop {
-        unsafe { std::alloc::alloc(Layout::from_size_align(2 ^ 8, 8).unwrap()) };
+        let _ = unsafe { std::alloc::alloc(Layout::from_size_align(2 ^ 8, 8).unwrap()) };
     }
 }