diff --git a/src/option_parser.cpp b/src/option_parser.cpp
index 17f0120b..484d0141 100644
--- a/src/option_parser.cpp
+++ b/src/option_parser.cpp
@@ -325,6 +325,7 @@ namespace options
   {
     const struct fuse_opt opts[] =
       {
+        FUSE_OPT_KEY("-d",MERGERFS_OPT_DEBUG),
         FUSE_OPT_KEY("-h",MERGERFS_OPT_HELP),
         FUSE_OPT_KEY("--help",MERGERFS_OPT_HELP),
         FUSE_OPT_KEY("-v",MERGERFS_OPT_VERSION),