diff --git a/lib/chibi/filesystem.stub b/lib/chibi/filesystem.stub
index ebd2f7be..69b50a31 100644
--- a/lib/chibi/filesystem.stub
+++ b/lib/chibi/filesystem.stub
@@ -3,7 +3,7 @@
 (c-system-include "unistd.h")
 (c-system-include "dirent.h")
 
-(define-c-struct DIR
+(define-c-type DIR
   finalizer: closedir)
 
 (define-c-struct dirent