---

yaml
---
r: 145831
b: refs/heads/try2
c: 649c175
h: refs/heads/master
i:
  145829: 5df7498
  145827: 9c6b2e0
  145823: 9bc546d
v: v3

Author: huonw

[refs]

@@ -5,7 +5,7 @@ refs/heads/snap-stage3: 78a7676898d9f80ab540c6df5d4c9ce35bb50463
 refs/heads/try: 519addf6277dbafccbb4159db4b710c37eaa2ec5
 refs/tags/release-0.1: 1f5c5126e96c79d22cb7862f75304136e204f105
 refs/heads/ndm: f3868061cd7988080c30d6d5bf352a5a5fe2460b
-refs/heads/try2: 38732c4b5cf778cb1b441bfc4290b3e3524b80c2
+refs/heads/try2: 649c1759e8b56f0ac31dd31e46eae81b7ffd1e2c
 refs/heads/dist-snap: ba4081a5a8573875fed17545846f6f6902c8ba8d
 refs/tags/release-0.2: c870d2dffb391e14efb05aa27898f1f6333a9596
 refs/tags/release-0.3: b5f0d0f648d9a6153664837026ba1be43d3e2503

branches/try2/src/libstd/rand/reader.rs

@@ -47,13 +47,17 @@ impl<R: Reader> ReaderRng<R> {
 
 impl<R: Reader> Rng for ReaderRng<R> {
     fn next_u32(&mut self) -> u32 {
+        // This is designed for speed: reading a LE integer on a LE
+        // platform just involves blitting the bytes into the memory
+        // of the u32, similarly for BE on BE; avoiding byteswapping.
         if cfg!(target_endian="little") {
             self.reader.read_le_u32_()
         } else {
             self.reader.read_be_u32_()
         }
     }
     fn next_u64(&mut self) -> u64 {
+        // see above for explanation.
         if cfg!(target_endian="little") {
             self.reader.read_le_u64_()
         } else {