diff --git a/test/ruby/test_thread.rb b/test/ruby/test_thread.rb
index c82018dc8e..e9bf1f16b6 100644
--- a/test/ruby/test_thread.rb
+++ b/test/ruby/test_thread.rb
@@ -176,6 +176,14 @@ class TestThread < Test::Unit::TestCase
     t2.kill if t2
   end
 
+  def test_new_symbol_proc
+    bug = '[ruby-core:80147] [Bug #13313]'
+    assert_ruby_status([], "#{<<-"begin;"}\n#{<<-'end;'}", bug)
+    begin;
+      exit("1" == Thread.start(1, &:to_s).value)
+    end;
+  end
+
   def test_join
     t = Thread.new { sleep }
     assert_nil(t.join(0.05))
diff --git a/thread.c b/thread.c
index 9840880925..fffce53675 100644
--- a/thread.c
+++ b/thread.c
@@ -555,10 +555,11 @@ thread_do_start(rb_thread_t *th, VALUE args)
 {
     native_set_thread_name(th);
     if (!th->first_func) {
+	const VALUE *ep = vm_proc_ep(th->first_proc);
 	rb_proc_t *proc;
 	GetProcPtr(th->first_proc, proc);
 	th->errinfo = Qnil;
-	th->root_lep = rb_vm_ep_local_ep(vm_proc_ep(th->first_proc));
+	th->root_lep = ep ? rb_vm_ep_local_ep(ep) : NULL;
 	th->root_svar = Qfalse;
 	EXEC_EVENT_HOOK(th, RUBY_EVENT_THREAD_BEGIN, th->self, 0, 0, 0, Qundef);
 	th->value = rb_vm_invoke_proc(th, proc,