diff --git a/src/libcore/ptr/mod.rs b/src/libcore/ptr/mod.rs
index 805404b101b7..0ee50966f968 100644
--- a/src/libcore/ptr/mod.rs
+++ b/src/libcore/ptr/mod.rs
@@ -1081,8 +1081,7 @@ fn mod_inv(x: usize, m: usize) -> usize {
                 // uses e.g., subtraction `mod n`. It is entirely fine to do them `mod
                 // usize::max_value()` instead, because we take the result `mod n` at the end
                 // anyway.
-                inverse = inverse.wrapping_mul(2usize.wrapping_sub(x.wrapping_mul(inverse)))
-                    & (going_mod - 1);
+                inverse = inverse.wrapping_mul(2usize.wrapping_sub(x.wrapping_mul(inverse)));
                 if going_mod >= m {
                     return inverse & (m - 1);
                 }