diff --git a/mjit.c b/mjit.c
index 3eb2ee8a50..be4bd9681e 100644
--- a/mjit.c
+++ b/mjit.c
@@ -118,7 +118,7 @@ mjit_update_references(const rb_iseq_t *iseq)
         return;
     CRITICAL_SECTION_START(4, "mjit_free_iseq");
     if (iseq->body->jit_unit) {
-        iseq->body->jit_unit->iseq = (rb_iseq_t *)rb_gc_new_location(iseq->body->jit_unit->iseq);
+        iseq->body->jit_unit->iseq = (rb_iseq_t *)rb_gc_new_location((VALUE)iseq->body->jit_unit->iseq);
     }
     CRITICAL_SECTION_FINISH(4, "mjit_free_iseq");
 }
@@ -236,7 +236,7 @@ create_unit(const rb_iseq_t *iseq)
         return;
 
     unit->id = current_unit_num++;
-    unit->iseq = iseq;
+    unit->iseq = (rb_iseq_t *)iseq;
     iseq->body->jit_unit = unit;
 }
 
diff --git a/mjit_worker.c b/mjit_worker.c
index 819a4a06ca..8b68cf01a0 100644
--- a/mjit_worker.c
+++ b/mjit_worker.c
@@ -128,7 +128,7 @@ struct rb_mjit_unit {
     int id;
     // Dlopen handle of the loaded object file.
     void *handle;
-    const rb_iseq_t *iseq;
+    rb_iseq_t *iseq;
 #ifndef _MSC_VER
     // This value is always set for `compact_all_jit_code`. Also used for lazy deletion.
     char *o_file;