diff --git a/Makefile b/Makefile
index 833ccffad6c..e93382855f4 100644
--- a/Makefile
+++ b/Makefile
@@ -114,7 +114,7 @@ endef
 #$(call get-source-dir,ret-variable-for-source-dir,package-dir,package-name)
 define get-source-dir
 	$(info getting source dir for package $(3) with dir $(2))
-	$(1) := $(shell if [[ "." == "$(2)" ]]; then \
+	$(1) := $(shell set -x; if [[ "." == "$(2)" ]]; then \
 		if [[ -d "./$(3)" ]]; then \
 			echo "--source-dir ./$(3)"; \
 		fi \