Auto merge of #45725 - alexcrichton:std-less-rand, r=dtolnay

Working towards a libc-less (wasm32) libstd

This is a series of commits I was able to extract from prepare to comiple libstd on a "bare libc-less" target, notably wasm32. The actual wasm32 bits I intend to send in a PR later, this is just some internal refactorings required for libstd to work with a `libc` that's empty and a few other assorted refactorings.

No functional change should be included in this PR for users of libstd, this is intended to just be internal refactorings.

1 files changed, 1 insertions, 3 deletions

diff --git a/src/libstd/sync/rwlock.rs b/src/libstd/sync/rwlock.rs
index d59a0b65a69..6216d78528d 100644
--- a/src/libstd/sync/rwlock.rs
+++ b/src/libstd/sync/rwlock.rs
@@ -554,8 +554,6 @@ impl<'a, T: ?Sized> Drop for RwLockWriteGuard<'a, T> {
 
 #[cfg(all(test, not(target_os = "emscripten")))]
 mod tests {
-    #![allow(deprecated)] // rand
-
     use rand::{self, Rng};
     use sync::mpsc::channel;
     use thread;
@@ -576,7 +574,7 @@ mod tests {
 
     #[test]
     fn frob() {
-        const N: usize = 10;
+        const N: u32 = 10;
         const M: usize = 1000;
 
         let r = Arc::new(RwLock::new(()));