diff --git a/include/ruby/ruby.h b/include/ruby/ruby.h
index 9b7c9842f8..b03c3cba00 100644
--- a/include/ruby/ruby.h
+++ b/include/ruby/ruby.h
@@ -2512,6 +2512,8 @@ rb_scan_args_set(int argc, const VALUE *argv,
 		 int f_var, int f_hash, int f_block,
 		 VALUE *vars[], char *fmt, int varc));
 
+PRINTF_ARGS(void rb_warn_deprecated(const char *fmt, const char *suggest, ...), 1, 3);
+
 inline int
 rb_scan_args_set(int argc, const VALUE *argv,
 		 int n_lead, int n_opt, int n_trail,
@@ -2569,7 +2571,7 @@ rb_scan_args_set(int argc, const VALUE *argv,
                     if (!keyword_given) {
                         /* Warn if treating positional as keyword, as in Ruby 3,
                            this will be an error */
-                        rb_warn("Using the last argument as keyword parameters is deprecated");
+                        rb_warn_deprecated("Using the last argument as keyword parameters", NULL);
                     }
                     argc--;
                 }
@@ -2584,7 +2586,7 @@ rb_scan_args_set(int argc, const VALUE *argv,
         }
         else if (f_hash && keyword_given && n_mand == argc) {
             /* Warn if treating keywords as positional, as in Ruby 3, this will be an error */
-            rb_warn("Passing the keyword argument as the last hash parameter is deprecated");
+            rb_warn_deprecated("Passing the keyword argument as the last hash parameter", NULL);
         }
     }
     if (f_hash && n_mand > 0 && n_mand == argc+1 && empty_keyword_given) {
@@ -2593,7 +2595,7 @@ rb_scan_args_set(int argc, const VALUE *argv,
         ptr[argc] = rb_hash_new();
         argc++;
         *(&argv) = ptr;
-        rb_warn("Passing the keyword argument as the last hash parameter is deprecated");
+        rb_warn_deprecated("Passing the keyword argument as the last hash parameter", NULL);
     }