Use libcore intrinsics instead

src/shims/mod.rs

@@ -41,7 +41,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
                 if stride >= a {
                     // This code was copied from the original `align_offset` implementation in
                     // rust/src/libcore/ptr/mod.rs, refer to it for its documentation
-                    use std::intrinsics::{unchecked_rem, cttz_nonzero};
+                    use core::intrinsics::{unchecked_rem, cttz_nonzero};
                     #[inline]
                     fn mod_inv(x: usize, m: usize) -> usize {
                         const INV_TABLE_MOD_16: [u8; 8] = [1, 11, 13, 7, 9, 3, 5, 15];