diff --git a/ext/-test-/cxxanyargs/cxxanyargs.cpp b/ext/-test-/cxxanyargs/cxxanyargs.cpp
index 46f4069f7f..9912a6694c 100644
--- a/ext/-test-/cxxanyargs/cxxanyargs.cpp
+++ b/ext/-test-/cxxanyargs/cxxanyargs.cpp
@@ -98,7 +98,7 @@ namespace test_rb_block_call {
     test(VALUE self)
     {
         const ID mid = rb_intern("each");
-        const VALUE argv[] = {};
+        const VALUE argv[] = { Qundef };
         rb_block_call(self, mid, 0, argv, RUBY_METHOD_FUNC(block), self); // old
         return rb_block_call(self, mid, 0, argv, block, self); // new
     }
diff --git a/include/ruby/backward/cxxanyargs.hpp b/include/ruby/backward/cxxanyargs.hpp
index 70191a91d0..1c36cda54f 100644
--- a/include/ruby/backward/cxxanyargs.hpp
+++ b/include/ruby/backward/cxxanyargs.hpp
@@ -84,7 +84,7 @@ rb_define_hooked_variable(const char *q, VALUE *w, type *e, void_type *r)
 /// @name Exceptions and tag jumps
 /// @{
 
-DEPRECATED_BY(::rb_block_call,)
+DEPRECATED_TYPE(("Use rb_block_call instead"),)
 /// @brief       Old way to implement iterators.
 /// @param[in]   q  A function that can yield.
 /// @param[in]   w  Passed to `q`.