diff --git a/flang/include/flang/Runtime/io-api.h b/flang/include/flang/Runtime/io-api.h
index ae4b85136a191..e298ab4c53d4a 100644
--- a/flang/include/flang/Runtime/io-api.h
+++ b/flang/include/flang/Runtime/io-api.h
@@ -23,7 +23,7 @@ class Descriptor;
 
 namespace Fortran::runtime::io {
 
-class NonTbpDefinedIoTable;
+struct NonTbpDefinedIoTable;
 class NamelistGroup;
 class IoStatementState;
 using Cookie = IoStatementState *;