diff --git a/parse.y b/parse.y
index e84468d2a5..dd55279118 100644
--- a/parse.y
+++ b/parse.y
@@ -3455,6 +3455,7 @@ block_param_def	: '|' opt_bv_decl '|'
 		    }
 		| tOROP
 		    {
+			p->cur_arg = 0;
 			p->max_numparam = ORDINAL_PARAM;
 		    /*%%%*/
 			$$ = 0;
diff --git a/test/ruby/test_syntax.rb b/test/ruby/test_syntax.rb
index 5fb4dfa64f..ba479fa459 100644
--- a/test/ruby/test_syntax.rb
+++ b/test/ruby/test_syntax.rb
@@ -241,6 +241,16 @@ class TestSyntax < Test::Unit::TestCase
       o.instance_eval("def foo(var: bar {|var| var}) var end")
     end
 
+    o = Object.new
+    assert_warn("") do
+      o.instance_eval("def foo(var: bar {| | var}) var end")
+    end
+
+    o = Object.new
+    assert_warn("") do
+      o.instance_eval("def foo(var: bar {|| var}) var end")
+    end
+
     o = Object.new
     assert_warn("") do
       o.instance_eval("def foo(var: def bar(var) var; end) var end")
@@ -296,6 +306,16 @@ class TestSyntax < Test::Unit::TestCase
       o.instance_eval("def foo(var = bar {|var| var}) var end")
     end
 
+    o = Object.new
+    assert_warn("") do
+      o.instance_eval("def foo(var = bar {| | var}) var end")
+    end
+
+    o = Object.new
+    assert_warn("") do
+      o.instance_eval("def foo(var = bar {|| var}) var end")
+    end
+
     o = Object.new
     assert_warn("") do
       o.instance_eval("def foo(var = def bar(var) var; end) var end")