diff --git a/crates/luaffi/src/string.rs b/crates/luaffi/src/string.rs
index 40646bb..33dc932 100644
--- a/crates/luaffi/src/string.rs
+++ b/crates/luaffi/src/string.rs
@@ -42,7 +42,7 @@ impl lua_buf {
         }
     }
 
-    #[cfg(feature = "option_string_ffi")]
+    #[cfg(feature = "option_string_abi")]
     pub(crate) fn null() -> Self {
         Self {
             __ptr: ptr::null(),
@@ -72,7 +72,7 @@ impl lua_buffer {
         }
     }
 
-    #[cfg(feature = "option_string_ffi")]
+    #[cfg(feature = "option_string_abi")]
     pub(crate) fn null() -> Self {
         Self {
             __ptr: ptr::null_mut(),