diff --git a/pkgs/racket-pkgs/racket-test/tests/racket/optimize.rktl b/pkgs/racket-pkgs/racket-test/tests/racket/optimize.rktl
index 1c79ac0429..b05c5368f9 100644
--- a/pkgs/racket-pkgs/racket-test/tests/racket/optimize.rktl
+++ b/pkgs/racket-pkgs/racket-test/tests/racket/optimize.rktl
@@ -6,6 +6,7 @@
 (require racket/flonum
          racket/extflonum
          racket/fixnum
+         racket/undefined
          racket/unsafe/ops
          compiler/zo-parse
          compiler/zo-marshal)
@@ -18,6 +19,7 @@
   (namespace-require 'racket/flonum)
   (namespace-require 'racket/extflonum)
   (namespace-require 'racket/fixnum)
+  (namespace-require 'racket/undefined)
   (eval '(define-values (prop:thing thing? thing-ref) 
            (make-struct-type-property 'thing)))
   (eval '(struct rock (x) #:property prop:thing 'yes))
@@ -99,11 +101,11 @@
                      (test v name ((eval `(lambda (y) (let ([x1 (fx+ (random 1) ',arg1)])
                                                         (,op x1 y))))
                                    arg2)))))]
-	 [bin-exact (lambda (v op arg1 arg2 [check-fixnum-as-bad? #f])
-		      (check-error-message op (eval `(lambda (x) (,op x ',arg2))))
-		      (check-error-message op (eval `(lambda (x) (,op ',arg1 x))))
-		      (check-error-message op (eval `(lambda (x y) (,op x y))) #:first-arg arg1)
-		      (check-error-message op (eval `(lambda (x y) (,op x y))) #:second-arg arg2)
+	 [bin-exact (lambda (v op arg1 arg2 [check-fixnum-as-bad? #f] #:bad-value [bad-value 'bad])
+		      (check-error-message op (eval `(lambda (x) (,op x ',arg2))) #:bad-value bad-value)
+		      (check-error-message op (eval `(lambda (x) (,op ',arg1 x))) #:bad-value bad-value)
+		      (check-error-message op (eval `(lambda (x y) (,op x y))) #:first-arg arg1 #:bad-value bad-value)
+		      (check-error-message op (eval `(lambda (x y) (,op x y))) #:second-arg arg2 #:bad-value bad-value)
                       (when check-fixnum-as-bad?
                         (check-error-message op (eval `(lambda (x) (,op x ',arg2))) #t)
                         (check-error-message op (eval `(lambda (x) (,op x 10))) #t)
@@ -790,6 +792,8 @@
       (bin-exact 1.1t0 'extflvector-ref (extflvector 1.1t0 2.2t0 3.3t0) 0 #t)
       (bin-exact 3.3t0 'extflvector-ref (extflvector 1.1t0 2.2t0 3.3t0) 2)
       (un-exact 3 'extflvector-length (extflvector 1.1t0 2.2t0 3.3t0) #t)
+
+      (bin-exact 5 'check-not-undefined 5 'check-not-undefined #:bad-value undefined)
       )
     
     (let ([test-setter
diff --git a/racket/src/racket/src/fun.c b/racket/src/racket/src/fun.c
index ef71fc5501..8eb4d06086 100644
--- a/racket/src/racket/src/fun.c
+++ b/racket/src/racket/src/fun.c
@@ -86,7 +86,7 @@ READ_ONLY Scheme_Object *scheme_values_func; /* the function bound to `values' *
 READ_ONLY Scheme_Object *scheme_procedure_p_proc;
 READ_ONLY Scheme_Object *scheme_procedure_arity_includes_proc;
 READ_ONLY Scheme_Object *scheme_void_proc;
-READ_ONLY Scheme_Object *scheme_check_not_undefined;
+READ_ONLY Scheme_Object *scheme_check_not_undefined_proc;
 READ_ONLY Scheme_Object *scheme_apply_proc;
 READ_ONLY Scheme_Object *scheme_call_with_values_proc; /* the function bound to `call-with-values' */
 READ_ONLY Scheme_Object *scheme_reduced_procedure_struct;
@@ -161,7 +161,6 @@ static Scheme_Object *extract_one_cc_mark (int argc, Scheme_Object *argv[]);
 static Scheme_Object *call_with_immediate_cc_mark (int argc, Scheme_Object *argv[]);
 static Scheme_Object *void_func (int argc, Scheme_Object *argv[]);
 static Scheme_Object *void_p (int argc, Scheme_Object *argv[]);
-static Scheme_Object *check_not_undefined (int argc, Scheme_Object *argv[]);
 static Scheme_Object *dynamic_wind (int argc, Scheme_Object *argv[]);
 #ifdef TIME_SYNTAX
 static Scheme_Object *time_apply(int argc, Scheme_Object *argv[]);
@@ -494,9 +493,11 @@ scheme_init_fun (Scheme_Env *env)
 
   /* adds the new primitive check-undefined to the kernel langauge
      check-undefined has an arity of 1 and no flags */
-  REGISTER_SO(scheme_check_not_undefined);
-  scheme_check_not_undefined = scheme_make_prim_w_arity(check_not_undefined, "check-not-undefined", 2, 2);
-  scheme_add_global_constant("check-not-undefined", scheme_check_not_undefined, env);
+  REGISTER_SO(scheme_check_not_undefined_proc);
+  o = scheme_make_prim_w_arity(scheme_check_not_undefined, "check-not-undefined", 2, 2);
+  scheme_check_not_undefined_proc = o;
+  SCHEME_PRIM_PROC_FLAGS(o) |= scheme_intern_prim_opt_flags(SCHEME_PRIM_IS_BINARY_INLINED);
+  scheme_add_global_constant("check-not-undefined", o, env);
 
   scheme_add_global_constant("undefined", scheme_undefined, env);
 
@@ -2533,8 +2534,8 @@ void_p (int argc, Scheme_Object *argv[])
   return SAME_OBJ(argv[0], scheme_void) ? scheme_true : scheme_false;
 }
 
-static Scheme_Object *
-check_not_undefined (int argc, Scheme_Object *argv[])
+Scheme_Object *
+scheme_check_not_undefined (int argc, Scheme_Object *argv[])
 {
   if (!SCHEME_SYMBOLP(argv[1]))
     scheme_wrong_contract("check-not-undefined", "symbol?", 1, argc, argv);
diff --git a/racket/src/racket/src/jit.h b/racket/src/racket/src/jit.h
index 3206fadbd6..d996d1b45e 100644
--- a/racket/src/racket/src/jit.h
+++ b/racket/src/racket/src/jit.h
@@ -367,6 +367,7 @@ struct scheme_jit_common_record {
 # endif
 #endif
   void *make_rest_list_code, *make_rest_list_clear_code;
+  void *call_check_not_defined_code;
 
   Continuation_Apply_Indirect continuation_apply_indirect_code;
 #ifdef MZ_USE_LWC
diff --git a/racket/src/racket/src/jit_ts.c b/racket/src/racket/src/jit_ts.c
index 6d30b865ea..f3262a461c 100644
--- a/racket/src/racket/src/jit_ts.c
+++ b/racket/src/racket/src/jit_ts.c
@@ -106,6 +106,7 @@ define_ts_iS_s(scheme_checked_integer_to_char, FSRC_MARKS)
 # ifndef CAN_INLINE_ALLOC
 define_ts_iSi_s(scheme_build_list_offset, FSRC_OTHER)
 # endif
+define_ts_iS_s(scheme_check_not_undefined, FSRC_MARKS)
 #endif
 
 #ifdef JITCALL_TS_PROCS
@@ -238,4 +239,5 @@ define_ts_s_s(scheme_box, FSRC_OTHER)
 # define ts_scheme_struct_setter scheme_struct_setter
 # define ts_scheme_checked_char_to_integer scheme_checked_char_to_integer
 # define ts_scheme_checked_integer_to_char scheme_checked_integer_to_char
+# define ts_scheme_check_not_undefined scheme_check_not_undefined
 #endif
diff --git a/racket/src/racket/src/jitcommon.c b/racket/src/racket/src/jitcommon.c
index 0c1212ab04..8ee590d1b8 100644
--- a/racket/src/racket/src/jitcommon.c
+++ b/racket/src/racket/src/jitcommon.c
@@ -3225,6 +3225,42 @@ static int common11(mz_jit_state *jitter, void *_data)
   return 1;
 }
 
+static int common12(mz_jit_state *jitter, void *_data)
+{
+  /* call_check_not_defined_code */
+  /* ares are in R0 and R1 */
+  {
+    GC_CAN_IGNORE jit_insn *refr USED_ONLY_FOR_FUTURES;
+
+    sjc.call_check_not_defined_code = jit_get_ip();
+
+    mz_prolog(JIT_R2);
+
+    jit_subi_p(JIT_RUNSTACK, JIT_RUNSTACK, WORDS_TO_BYTES(2));
+    JIT_UPDATE_THREAD_RSPTR();
+
+    jit_stxi_p(WORDS_TO_BYTES(1), JIT_RUNSTACK, JIT_R1);
+    jit_str_p(JIT_RUNSTACK, JIT_R0);
+
+    CHECK_LIMIT();
+    jit_movi_i(JIT_R0, 2);
+    mz_prepare(2);
+    jit_pusharg_p(JIT_RUNSTACK);
+    jit_pusharg_i(JIT_R0);
+    mz_finish_prim_lwe(ts_scheme_check_not_undefined, refr);
+
+    jit_addi_p(JIT_RUNSTACK, JIT_RUNSTACK, WORDS_TO_BYTES(2));
+    JIT_UPDATE_THREAD_RSPTR();
+
+    mz_epilog(JIT_R2);
+
+    scheme_jit_register_sub_func(jitter, sjc.call_check_not_defined_code, scheme_false);
+    CHECK_LIMIT();
+  }
+
+  return 1;
+}
+
 int scheme_do_generate_common(mz_jit_state *jitter, void *_data)
 {
   if (!common0(jitter, _data)) return 0;
@@ -3243,6 +3279,7 @@ int scheme_do_generate_common(mz_jit_state *jitter, void *_data)
   if (!common9(jitter, _data)) return 0;
   if (!common10(jitter, _data)) return 0;
   if (!common11(jitter, _data)) return 0;
+  if (!common12(jitter, _data)) return 0;
   return 1;
 }
 
diff --git a/racket/src/racket/src/jitinline.c b/racket/src/racket/src/jitinline.c
index 58bc9f30a1..cbcd3d2d7d 100644
--- a/racket/src/racket/src/jitinline.c
+++ b/racket/src/racket/src/jitinline.c
@@ -3526,6 +3526,45 @@ int scheme_generate_inlined_binary(mz_jit_state *jitter, Scheme_App3_Rec *app, i
       (void)jit_calli(sjc.proc_arity_includes_code);
       jit_movr_p(dest, JIT_R0);
 
+      return 1;
+    } else if (IS_NAMED_PRIM(rator, "check-not-undefined")) {
+      if (SCHEME_SYMBOLP(app->rand2)) {
+        GC_CAN_IGNORE jit_insn *ref, *ref2;
+
+        LOG_IT(("inlined check-not-undefined\n"));
+
+        mz_runstack_skipped(jitter, 2);
+        scheme_generate_non_tail(app->rand1, jitter, 0, 1, 0); /* no sync... */
+        mz_runstack_unskipped(jitter, 2);
+        CHECK_LIMIT();
+
+        mz_rs_sync_fail_branch();
+
+        __START_TINY_JUMPS__(1);
+        ref = jit_bmsi_ul(jit_forward(), JIT_R0, 0x1);
+        ref2 = mz_bnei_t(jit_forward(), JIT_R0, scheme_undefined_type, JIT_R2);
+        __END_TINY_JUMPS__(1);
+
+        scheme_mz_load_retained(jitter, JIT_R1, app->rand2);
+        (void)jit_calli(sjc.call_check_not_defined_code);
+        /* never returns */
+
+        __START_TINY_JUMPS__(1);
+        mz_patch_branch(ref);
+        mz_patch_branch(ref2);
+        __END_TINY_JUMPS__(1);
+        CHECK_LIMIT();
+      } else {
+        scheme_generate_two_args(app->rand1, app->rand2, jitter, 1, 2);
+        CHECK_LIMIT();
+
+        mz_rs_sync();
+
+        (void)jit_calli(sjc.call_check_not_defined_code);
+      }
+
+      jit_movr_p(dest, JIT_R0);
+
       return 1;
     } else if (IS_NAMED_PRIM(rator, "values")) {
       Scheme_Object *args[3];
diff --git a/racket/src/racket/src/letrec_check.c b/racket/src/racket/src/letrec_check.c
index 0875ef83ab..9522290e7b 100644
--- a/racket/src/racket/src/letrec_check.c
+++ b/racket/src/racket/src/letrec_check.c
@@ -737,7 +737,7 @@ Scheme_Object *letrec_check_local(Scheme_Object *o, Letrec_Check_Frame *frame,
         
         app3 = MALLOC_ONE_TAGGED(Scheme_App3_Rec);
         app3->iso.so.type = scheme_application3_type;
-        app3->rator = scheme_check_not_undefined;
+        app3->rator = scheme_check_not_undefined_proc;
         app3->rand1 = o;
         app3->rand2 = name;
         
diff --git a/racket/src/racket/src/optimize.c b/racket/src/racket/src/optimize.c
index c42b64cf94..91ef629d6c 100644
--- a/racket/src/racket/src/optimize.c
+++ b/racket/src/racket/src/optimize.c
@@ -2577,7 +2577,7 @@ static Scheme_Object *optimize_application3(Scheme_Object *o, Optimize_Info *inf
 
   app = (Scheme_App3_Rec *)o;
 
-  if (SAME_OBJ(app->rator, scheme_check_not_undefined)
+  if (SAME_OBJ(app->rator, scheme_check_not_undefined_proc)
       && SCHEME_SYMBOLP(app->rand2)) {
     scheme_log(info->logger,
                SCHEME_LOG_WARNING,
diff --git a/racket/src/racket/src/schpriv.h b/racket/src/racket/src/schpriv.h
index 34c275fc7b..5f560321b3 100644
--- a/racket/src/racket/src/schpriv.h
+++ b/racket/src/racket/src/schpriv.h
@@ -435,7 +435,7 @@ extern Scheme_Object *scheme_values_func;
 extern Scheme_Object *scheme_procedure_p_proc;
 extern Scheme_Object *scheme_procedure_arity_includes_proc;
 extern Scheme_Object *scheme_void_proc;
-extern Scheme_Object *scheme_check_not_undefined;
+extern Scheme_Object *scheme_check_not_undefined_proc;
 extern Scheme_Object *scheme_pair_p_proc;
 extern Scheme_Object *scheme_mpair_p_proc;
 extern Scheme_Object *scheme_unsafe_cons_list_proc;
@@ -3987,6 +3987,8 @@ Scheme_Object *scheme_procedure_arity_includes(int argc, Scheme_Object *argv[]);
 Scheme_Object *scheme_checked_char_to_integer (int argc, Scheme_Object *argv[]);
 Scheme_Object *scheme_checked_integer_to_char (int argc, Scheme_Object *argv[]);
 
+Scheme_Object *scheme_check_not_undefined (int argc, Scheme_Object *argv[]);
+
 Scheme_Object *scheme_chaperone_vector_copy(Scheme_Object *obj);
 Scheme_Object *scheme_chaperone_hash_table_copy(Scheme_Object *obj);