Make std::hash::RandomState not be align(8) to work around TLS issues on 95

At least on Windows 95 RTM, the TLS variables are only aligned to a 4 byte boundary. Unclear if this affects other systems, but NT4 is fine.

Author: seritools

library/std/src/hash/random.rs

@@ -65,13 +65,16 @@ impl RandomState {
         // iteration order allows a form of DOS attack. To counter that we
         // increment one of the seeds on every RandomState creation, giving
         // every corresponding HashMap a different iteration order.
-        thread_local!(static KEYS: Cell<(u64, u64)> = {
+        thread_local!(static KEYS: Cell<[u8; 16]> = {
             Cell::new(hashmap_random_keys())
         });
 
         KEYS.with(|keys| {
-            let (k0, k1) = keys.get();
-            keys.set((k0.wrapping_add(1), k1));
+            let [n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11, n12, n13, n14, n15] = keys.get();
+            let k0 = u64::from_ne_bytes([n0, n1, n2, n3, n4, n5, n6, n7]);
+            let k1 = u64::from_ne_bytes([n8, n9, n10, n11, n12, n13, n14, n15]);
+            let [n0, n1, n2, n3, n4, n5, n6, n7] = k0.wrapping_add(1).to_ne_bytes();
+            keys.set([n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11, n12, n13, n14, n15]);
             RandomState { k0, k1 }
         })
     }

library/std/src/sys/random/mod.rs

@@ -89,10 +89,8 @@ cfg_if::cfg_if! {
     all(target_family = "wasm", target_os = "unknown"),
     target_os = "xous",
 )))]
-pub fn hashmap_random_keys() -> (u64, u64) {
+pub fn hashmap_random_keys() -> [u8; 16] {
     let mut buf = [0; 16];
     fill_bytes(&mut buf);
-    let k1 = u64::from_ne_bytes(buf[..8].try_into().unwrap());
-    let k2 = u64::from_ne_bytes(buf[8..].try_into().unwrap());
-    (k1, k2)
+    buf
 }