diff --git a/src/xenia/cpu/hir/value.h b/src/xenia/cpu/hir/value.h
index ff41edf3b..dcc95ca8c 100644
--- a/src/xenia/cpu/hir/value.h
+++ b/src/xenia/cpu/hir/value.h
@@ -170,6 +170,7 @@ class Value {
     constant.v128 = value;
   }
   void set_from(const Value* other) {
+    assert_true(other->IsConstant());
     type = other->type;
     flags = other->flags;
     constant.v128 = other->constant.v128;