diff --git a/repos/dde_linux/ports/dde_linux.hash b/repos/dde_linux/ports/dde_linux.hash
index cc4e675c32..3bfa77e485 100644
--- a/repos/dde_linux/ports/dde_linux.hash
+++ b/repos/dde_linux/ports/dde_linux.hash
@@ -1 +1 @@
-7f4e92802b6293f4816c0f366111b554109eec99
+aafe49e012e64e25f60c47fd53f4b58e8eb70f3e
diff --git a/repos/dde_linux/ports/dde_linux.port b/repos/dde_linux/ports/dde_linux.port
index 5b5bbfb796..e37ad83c87 100644
--- a/repos/dde_linux/ports/dde_linux.port
+++ b/repos/dde_linux/ports/dde_linux.port
@@ -6,8 +6,11 @@ DOWNLOADS   := dwc_otg.git usb.archive lxip.archive wifi.archive \
 #
 # Tools
 #
-FLEX        ?= flex
-YACC        ?= bison
+$(call check_tool,flex)
+$(call check_tool,bison)
+
+FLEX = flex
+YACC = bison
 
 #
 # The git checkout checks for the existence of SRC_DIR, which is created by the