1 files changed, 1 insertions, 0 deletions
diff --git a/internal.h b/internal.h
index d52b2e9442..e196b23cd2 100644
--- a/internal.h
+++ b/internal.h
@@ -283,6 +283,7 @@ void ruby_set_inplace_mode(const char *);
 ssize_t rb_io_bufread(VALUE io, void *buf, size_t size);
 void rb_stdio_set_default_encoding(void);
 void rb_write_error_str(VALUE mesg);
+VALUE rb_io_flush_raw(VALUE, int);
 
 /* iseq.c */
 VALUE rb_iseq_clone(VALUE iseqval, VALUE newcbase);