diff --git a/src/libcore/ptr.rs b/src/libcore/ptr.rs
index 37e9d18095f82..42aef3ab3dd75 100644
--- a/src/libcore/ptr.rs
+++ b/src/libcore/ptr.rs
@@ -220,7 +220,7 @@ impl<T: ?Sized> *const T {
     /// ```
     /// let s: &str = "Follow the rabbit";
     /// let ptr: *const u8 = s.as_ptr();
-    /// assert!(ptr.is_null() == false);
+    /// assert!(!ptr.is_null());
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
@@ -306,7 +306,7 @@ impl<T: ?Sized> *mut T {
     /// ```
     /// let mut s = [1, 2, 3];
     /// let ptr: *mut u32 = s.as_mut_ptr();
-    /// assert!(ptr.is_null() == false);
+    /// assert!(!ptr.is_null());
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
diff --git a/src/libstd/fs.rs b/src/libstd/fs.rs
index d8af73816c9c0..c4d6cb33365d0 100644
--- a/src/libstd/fs.rs
+++ b/src/libstd/fs.rs
@@ -1708,7 +1708,7 @@ mod tests {
         let tmpdir = tmpdir();
         let dir = &tmpdir.join("fileinfo_false_on_dir");
         check!(fs::create_dir(dir));
-        assert!(dir.is_file() == false);
+        assert!(!dir.is_file());
         check!(fs::remove_dir(dir));
     }
 
diff --git a/src/libtest/lib.rs b/src/libtest/lib.rs
index e7fe128a7ae8d..e78fd0dea292a 100644
--- a/src/libtest/lib.rs
+++ b/src/libtest/lib.rs
@@ -1509,7 +1509,7 @@ mod tests {
 
         assert_eq!(filtered.len(), 1);
         assert_eq!(filtered[0].desc.name.to_string(), "1");
-        assert!(filtered[0].desc.ignore == false);
+        assert!(!filtered[0].desc.ignore);
     }
 
     #[test]
diff --git a/src/test/run-pass/specialization/specialization-cross-crate-defaults.rs b/src/test/run-pass/specialization/specialization-cross-crate-defaults.rs
index bc695ea821d0a..62c7e3e2e4431 100644
--- a/src/test/run-pass/specialization/specialization-cross-crate-defaults.rs
+++ b/src/test/run-pass/specialization/specialization-cross-crate-defaults.rs
@@ -26,12 +26,12 @@ impl Foo for LocalOverride {
 }
 
 fn test_foo() {
-    assert!(0i8.foo() == false);
-    assert!(0i32.foo() == false);
-    assert!(0i64.foo() == true);
+    assert!(!0i8.foo());
+    assert!(!0i32.foo());
+    assert!(0i64.foo());
 
-    assert!(LocalDefault.foo() == false);
-    assert!(LocalOverride.foo() == true);
+    assert!(!LocalDefault.foo());
+    assert!(LocalOverride.foo());
 }
 
 fn test_bar() {
diff --git a/src/test/run-pass/specialization/specialization-default-methods.rs b/src/test/run-pass/specialization/specialization-default-methods.rs
index 3f0f21ff03f27..9cfc6aabbb4f2 100644
--- a/src/test/run-pass/specialization/specialization-default-methods.rs
+++ b/src/test/run-pass/specialization/specialization-default-methods.rs
@@ -35,9 +35,9 @@ impl Foo for i64 {
 }
 
 fn test_foo() {
-    assert!(0i8.foo() == false);
-    assert!(0i32.foo() == false);
-    assert!(0i64.foo() == true);
+    assert!(!0i8.foo());
+    assert!(!0i32.foo());
+    assert!(0i64.foo());
 }
 
 // Next, test mixture of explicit `default` and provided methods: