1 files changed, 1 insertions, 1 deletions
diff --git a/perlio.c b/perlio.c
index 90867dec9a..549a1877b0 100644
--- a/perlio.c
+++ b/perlio.c
@@ -426,7 +426,7 @@ PerlIO_list_push(PerlIO_list_t *list,PerlIO_funcs *funcs,SV *arg)
 
 
 void
-PerlIO_cleanup_layers(pTHXo_ void *data)
+PerlIO_cleanup_layers(pTHX_ void *data)
 {
 #if 0
  PerlIO_known_layers = Nullhv;