diff --git a/Pmodules/libpbuild.bash b/Pmodules/libpbuild.bash
index bb25331..cba4659 100644
--- a/Pmodules/libpbuild.bash
+++ b/Pmodules/libpbuild.bash
@@ -793,6 +793,7 @@ _build_module() {
 	#	$1	module name
 	#
 	bm::is_loaded() {
+		[[ -v LOADEDMODULES ]] || return 1
 		[[ :${LOADEDMODULES}: =~ :$1: ]] && return 0
 		[[ :${LOADEDMODULES}: =~ :$1.lua: ]] && return 0
 		return 1