diff --git a/rts/js/mem.js b/rts/js/mem.js
index 44c5c37ac4..1f150c5d55 100644
--- a/rts/js/mem.js
+++ b/rts/js/mem.js
@@ -1,5 +1,5 @@
 //#OPTIONS:CPP
-//#OPTIONS:EMCC:EXPORTED_RUNTIME_METHODS=addFunction,removeFunction,getEmptyTableSlot
+//#OPTIONS:EMCC:EXPORTED_RUNTIME_METHODS=addFunction,removeFunction,getEmptyTableSlot,HEAP8,HEAPU8
 
 // #define GHCJS_TRACE_META 1