diff --git a/src/tools/miri/src/shims/intrinsics/simd.rs b/src/tools/miri/src/shims/intrinsics/simd.rs
index 0dc669849fe..200f37efa27 100644
--- a/src/tools/miri/src/shims/intrinsics/simd.rs
+++ b/src/tools/miri/src/shims/intrinsics/simd.rs
@@ -506,8 +506,11 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 assert_eq!(index_len as u64, dest_len);
 
                 for i in 0..dest_len {
-                    let src_index: u64 =
-                        index[i as usize].unwrap_leaf().try_to_u32().unwrap().into();
+                    let src_index: u64 = index[usize::try_from(i).unwrap()]
+                        .unwrap_leaf()
+                        .try_to_u32()
+                        .unwrap()
+                        .into();
                     let dest = this.project_index(&dest, i)?;
 
                     let val = if src_index < left_len {