Tsan test fix

Author: korken89

tests/tsan.rs

@@ -166,7 +166,7 @@ fn unchecked() {
 
     let mut rb: spsc::Queue<u8, N> = spsc::Queue::new();
 
-    for _ in 0..N / 2 {
+    for _ in 0..N / 2 - 1 {
         rb.enqueue(1).unwrap();
     }
 
@@ -175,24 +175,24 @@ fn unchecked() {
 
         Pool::new(2).scoped(move |scope| {
             scope.execute(move || {
-                for _ in 0..N / 2 {
+                for _ in 0..N / 2 - 1 {
                     p.enqueue(2).unwrap();
                 }
             });
 
             scope.execute(move || {
                 let mut sum: usize = 0;
 
-                for _ in 0..N / 2 {
+                for _ in 0..N / 2 - 1 {
                     sum = sum.wrapping_add(usize::from(c.dequeue().unwrap()));
                 }
 
-                assert_eq!(sum, N / 2);
+                assert_eq!(sum, N / 2 - 1);
             });
         });
     }
 
-    assert_eq!(rb.len(), N / 2);
+    assert_eq!(rb.len(), N / 2 - 1);
 }
 
 #[test]