1 files changed, 38 insertions, 0 deletions
diff --git a/js/public/shadow/Symbol.h b/js/public/shadow/Symbol.h
new file mode 100644
index 0000000000..a4b40139cc
--- /dev/null
+++ b/js/public/shadow/Symbol.h
@@ -0,0 +1,38 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=8 sts=2 et sw=2 tw=80:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/* Shadow definition of |JS::Symbol| innards.  Do not use this directly! */
+
+#ifndef js_shadow_Symbol_h
+#define js_shadow_Symbol_h
+
+#include <stdint.h>  // uint32_t
+
+namespace js {
+namespace gc {
+struct Cell;
+}  // namespace gc
+}  // namespace js
+
+namespace JS {
+
+namespace shadow {
+
+struct Symbol {
+  void* _1;
+  uint32_t code_;
+  static constexpr uint32_t WellKnownAPILimit = 0x80000000;
+
+  static bool isWellKnownSymbol(const js::gc::Cell* cell) {
+    return reinterpret_cast<const Symbol*>(cell)->code_ < WellKnownAPILimit;
+  }
+};
+
+}  // namespace shadow
+
+}  // namespace JS
+
+#endif  // js_shadow_Symbol_h