auto merge of #21288 : brson/rust/snaps, r=alexcrichton

This fixes the issues mentioned in #21236, as well as the one #21230 where `CFG_BOOTSTRAP_KEY` was being set to simply 'N'. It changes the build such that `RUSTC_BOOTSTRAP_KEY` is only exported on -beta and -stable, so that the behavior of the -dev, -nightly, and snapshot compilers is the same everywhere.

Haven't run it completely through 'make check' yet, but the I have verified that the aforementioned issues are fixed.

r? @alexcrichton cc @eddyb

Author: bors

configure

@@ -612,7 +612,7 @@ putvar CFG_RELEASE_CHANNEL
 # channel.
 # Basing CFG_BOOTSTRAP_KEY on CFG_BOOTSTRAP_KEY lets it get picked up
 # during a Makefile reconfig.
-CFG_BOOTSTRAP_KEY="${CFG_BOOTSTRAP_KEY-`date +%N`}"
+CFG_BOOTSTRAP_KEY="${CFG_BOOTSTRAP_KEY-`date +%H:%M:%S`}"
 putvar CFG_BOOTSTRAP_KEY
 
 step_msg "looking for build programs"

mk/main.mk

@@ -330,10 +330,10 @@ ifdef CFG_DISABLE_UNSTABLE_FEATURES
 CFG_INFO := $(info cfg: disabling unstable features (CFG_DISABLE_UNSTABLE_FEATURES))
 # Turn on feature-staging
 export CFG_DISABLE_UNSTABLE_FEATURES
-endif
 # Subvert unstable feature lints to do the self-build
-export CFG_BOOTSTRAP_KEY
 export RUSTC_BOOTSTRAP_KEY:=$(CFG_BOOTSTRAP_KEY)
+endif
+export CFG_BOOTSTRAP_KEY
 
 ######################################################################
 # Per-stage targets and runner

src/compiletest/compiletest.rs

@@ -13,6 +13,7 @@
 #![feature(slicing_syntax, unboxed_closures)]
 #![feature(box_syntax)]
 #![feature(int_uint)]
+#![allow(unstable)]
 
 #![deny(warnings)]
 

src/driver/driver.rs

@@ -8,6 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+#![allow(unstable)]
+
 #[cfg(rustdoc)]
 extern crate "rustdoc" as this;
 

src/liballoc/boxed.rs

@@ -117,14 +117,6 @@ impl<T: ?Sized + Ord> Ord for Box<T> {
 #[stable]
 impl<T: ?Sized + Eq> Eq for Box<T> {}
 
-#[cfg(stage0)]
-impl<S: hash::Writer, T: ?Sized + Hash<S>> Hash<S> for Box<T> {
-    #[inline]
-    fn hash(&self, state: &mut S) {
-        (**self).hash(state);
-    }
-}
-#[cfg(not(stage0))]
 impl<S: hash::Hasher, T: ?Sized + Hash<S>> Hash<S> for Box<T> {
     #[inline]
     fn hash(&self, state: &mut S) {

src/liballoc/lib.rs

@@ -66,6 +66,7 @@
 
 #![no_std]
 #![allow(unknown_features)]
+#![allow(unstable)]
 #![feature(lang_items, unsafe_destructor)]
 #![feature(box_syntax)]
 #![feature(optin_builtin_traits)]

src/liballoc/rc.rs

@@ -686,14 +686,6 @@ impl<T: Ord> Ord for Rc<T> {
 }
 
 // FIXME (#18248) Make `T` `Sized?`
-#[cfg(stage0)]
-impl<S: hash::Writer, T: Hash<S>> Hash<S> for Rc<T> {
-    #[inline]
-    fn hash(&self, state: &mut S) {
-        (**self).hash(state);
-    }
-}
-#[cfg(not(stage0))]
 impl<S: hash::Hasher, T: Hash<S>> Hash<S> for Rc<T> {
     #[inline]
     fn hash(&self, state: &mut S) {

src/libarena/lib.rs

@@ -34,6 +34,7 @@
 #![feature(box_syntax)]
 #![allow(unknown_features)] #![feature(int_uint)]
 #![allow(missing_docs)]
+#![allow(unstable)]
 
 extern crate alloc;
 

src/libcollections/btree/map.rs

@@ -24,8 +24,6 @@ use core::cmp::Ordering;
 use core::default::Default;
 use core::fmt::Show;
 use core::hash::{Hash, Hasher};
-#[cfg(stage0)]
-use core::hash::Writer;
 use core::iter::{Map, FromIterator};
 use core::ops::{Index, IndexMut};
 use core::{iter, fmt, mem};
@@ -822,16 +820,6 @@ impl<K: Ord, V> Extend<(K, V)> for BTreeMap<K, V> {
 }
 
 #[stable]
-#[cfg(stage0)]
-impl<S: Writer, K: Hash<S>, V: Hash<S>> Hash<S> for BTreeMap<K, V> {
-    fn hash(&self, state: &mut S) {
-        for elt in self.iter() {
-            elt.hash(state);
-        }
-    }
-}
-#[stable]
-#[cfg(not(stage0))]
 impl<S: Hasher, K: Hash<S>, V: Hash<S>> Hash<S> for BTreeMap<K, V> {
     fn hash(&self, state: &mut S) {
         for elt in self.iter() {

src/libcollections/lib.rs

@@ -28,6 +28,7 @@
 #![feature(unboxed_closures)]
 #![feature(old_impl_check)]
 #![allow(unknown_features)] #![feature(int_uint)]
+#![allow(unstable)]
 #![no_std]
 
 #[macro_use]