diff --git a/javascript/Makefile b/javascript/Makefile
index a6760dfb..97f42e98 100644
--- a/javascript/Makefile
+++ b/javascript/Makefile
@@ -9,6 +9,8 @@ asm:
 		-g0 \
 		-Os \
 		-flto \
+		-fno-rtti \
+		-DEMSCRIPTEN_HAS_UNBOUND_TYPE_NAMES=0 \
 		--closure 1 \
 		--memory-init-file 0 \
 		-s WASM=0 \