1 files changed, 1 insertions, 1 deletions
diff --git a/process.c b/process.c
index 37299174fb..bd078a3c8d 100644
--- a/process.c
+++ b/process.c
@@ -509,7 +509,7 @@ rb_f_fork(obj)
 #ifdef linux
 	after_exec();
 #endif
-	if (rb_iterator_p()) {
+	if (rb_block_given_p()) {
 	    rb_yield(Qnil);
 	    _exit(0);
 	}