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* Lots of core prelude imports removed
* Makefile support for MSVC env vars and Rust crates removed
* Makefile support for morestack removed

src/liballoc/arc.rs

@@ -71,9 +71,6 @@
 
 use boxed::Box;
 
-#[cfg(stage0)]
-use core::prelude::v1::*;
-
 use core::atomic;
 use core::atomic::Ordering::{Relaxed, Release, Acquire, SeqCst};
 use core::fmt;