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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/libstd/sys/unix/os_str.rs

@@ -11,9 +11,6 @@
 /// The underlying OsString/OsStr implementation on Unix systems: just
 /// a `Vec<u8>`/`[u8]`.
 
-#[cfg(stage0)]
-use core::prelude::v1::*;
-
 use borrow::Cow;
 use fmt::{self, Debug};
 use vec::Vec;