diff --git a/block/src/vhdx/vhdx_header.rs b/block/src/vhdx/vhdx_header.rs
index b21f7a0c2..40031c8ca 100644
--- a/block/src/vhdx/vhdx_header.rs
+++ b/block/src/vhdx/vhdx_header.rs
@@ -90,7 +90,7 @@ pub type Result<T> = std::result::Result<T, VhdxHeaderError>;
 
 #[derive(Clone, Debug)]
 pub struct FileTypeIdentifier {
-    pub signature: u64,
+    pub _signature: u64,
 }
 
 impl FileTypeIdentifier {
@@ -98,14 +98,14 @@ impl FileTypeIdentifier {
     pub fn new(f: &mut File) -> Result<FileTypeIdentifier> {
         f.seek(SeekFrom::Start(FILE_START))
             .map_err(VhdxHeaderError::SeekFileTypeIdentifier)?;
-        let signature = f
+        let _signature = f
             .read_u64::<LittleEndian>()
             .map_err(VhdxHeaderError::ReadFileTypeIdentifier)?;
-        if signature != VHDX_SIGN {
+        if _signature != VHDX_SIGN {
             return Err(VhdxHeaderError::InvalidVHDXSign);
         }
 
-        Ok(FileTypeIdentifier { signature })
+        Ok(FileTypeIdentifier { _signature })
     }
 }