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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/time/duration.rs

@@ -8,9 +8,6 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#[cfg(stage0)]
-use prelude::v1::*;
-
 use ops::{Add, Sub, Mul, Div};
 use sys::time::SteadyTime;