diff --git a/rust/src/fileio_backend.rs b/rust/src/fileio_backend.rs
index 3f8058138..4bb84943c 100644
--- a/rust/src/fileio_backend.rs
+++ b/rust/src/fileio_backend.rs
@@ -1049,7 +1049,7 @@ mod tests {
         let mapped = unsafe { std::slice::from_raw_parts(buffer.cast::<u8>(), mapped_size) };
         assert_eq!(mapped, payload);
 
-        let mut dict_handle = 1usize as *mut c_void;
+        let mut dict_handle = ptr::dangling_mut::<c_void>();
         unsafe {
             FIO_rust_freeDict(
                 FIO_MMAP_DICT,
@@ -1074,7 +1074,7 @@ mod tests {
         assert!(!allocation.is_null());
         let mut buffer = allocation;
         let mut buffer_size = 16;
-        let mut dict_handle = 1usize as *mut c_void;
+        let mut dict_handle = ptr::dangling_mut::<c_void>();
 
         unsafe {
             FIO_rust_freeDict(
diff --git a/rust/src/zstd_compress.rs b/rust/src/zstd_compress.rs
index e679a3475..db57ae118 100644
--- a/rust/src/zstd_compress.rs
+++ b/rust/src/zstd_compress.rs
@@ -4573,7 +4573,7 @@ mod tests {
     #[test]
     fn one_shot_promotes_nonfirst_rle_blocks() {
         let mut input = vec![b'B'; 256 * 1024 - 2];
-        input.extend(std::iter::repeat(b'A').take(100 * 1024));
+        input.extend(std::iter::repeat_n(b'A', 100 * 1024));
 
         let compressed = compress_input(&input, 1);
         assert!(compressed.len() <= 46);