diff --git a/src/libcore/alloc.rs b/src/libcore/alloc.rs
index cee9b4eebe66e0aa34b89b20069b5c080d0a710a..20248f7f6c13e374e471f423a37b48ef14556f24 100644
--- a/src/libcore/alloc.rs
+++ b/src/libcore/alloc.rs
@@ -137,7 +137,7 @@ pub fn new<T>() -> Self {
     #[inline]
     pub fn for_value<T: ?Sized>(t: &T) -> Self {
         let (size, align) = (mem::size_of_val(t), mem::align_of_val(t));
-        // See rationale in `new` for why this us using an unsafe variant below
+        // See rationale in `new` for why this is using an unsafe variant below
         debug_assert!(Layout::from_size_align(size, align).is_ok());
         unsafe {
             Layout::from_size_align_unchecked(size, align)
@@ -196,7 +196,7 @@ pub fn padding_needed_for(&self, align: usize) -> usize {
         //    valid.
         //
         // 2. `len + align - 1` can overflow by at most `align - 1`,
-        //    so the &-mask wth `!(align - 1)` will ensure that in the
+        //    so the &-mask with `!(align - 1)` will ensure that in the
         //    case of overflow, `len_rounded_up` will itself be 0.
         //    Thus the returned padding, when added to `len`, yields 0,
         //    which trivially satisfies the alignment `align`.