diff --git a/Makefile b/Makefile
index 9d77500a..4cfc2fa5 100644
--- a/Makefile
+++ b/Makefile
@@ -176,6 +176,7 @@ CCOPTS_SHARED += -DDUK_OPT_DEBUG_BUFSIZE=512
 #CCOPTS_SHARED += -DDUK_OPT_NO_JSONX
 #CCOPTS_SHARED += -DDUK_OPT_NO_JSONC
 #CCOPTS_SHARED += -DDUK_OPT_FUNC_NONSTD_CALLER_PROPERTY
+#CCOPTS_SHARED += -DDUK_OPT_FUNC_NONSTD_SOURCE_PROPERTY
 #CCOPTS_SHARED += -DDUK_OPT_NO_ARRAY_SPLICE_NONSTD_DELCOUNT
 #CCOPTS_SHARED += -DDUK_OPT_NO_ZERO_BUFFER_DATA
 #CCOPTS_SHARED += -DDUK_CMDLINE_BAREBONES