diff --git a/src/haiku_support.cc b/src/haiku_support.cc
index 105da3969ff..5dfb25d6dd7 100644
--- a/src/haiku_support.cc
+++ b/src/haiku_support.cc
@@ -2989,7 +2989,7 @@ class EmacsFilePanelCallbackLooper : public BLooper
     BEntry entry;
     BPath path;
     entry_ref ref;
-    int old_what;
+    int32 old_what;
 
     if (msg->what == FILE_PANEL_SELECTION
 	|| ((msg->FindInt32 ("old_what", &old_what) == B_OK