make: fix unexpected operator warning

diff --git a/components/app_update/Makefile.projbuild b/components/app_update/Makefile.projbuild
index c9ee59137309349d71b1c81a4b127f5c2f87b7e1..26a987ac7c7a18adb7ee5877202e51ab45bf2327 100644 (file)
--- a/components/app_update/Makefile.projbuild
+++ b/components/app_update/Makefile.projbuild
@@ -9,11 +9,11 @@ PARTTOOL_PY := $(PYTHON) $(IDF_PATH)/components/partition_table/parttool.py
 BLANK_OTA_DATA_FILE = $(BUILD_DIR_BASE)/ota_data_initial.bin
 
 $(BLANK_OTA_DATA_FILE): partition_table_get_info $(PARTITION_TABLE_BIN) | check_python_dependencies
-       $(shell if [ $(OTA_DATA_OFFSET) != "" ] && [ $(OTA_DATA_SIZE) != "" ]; then \
+       $(shell if [ "$(OTA_DATA_OFFSET)" != "" ] && [ "$(OTA_DATA_SIZE)" != "" ]; then \
                                $(PARTTOOL_PY) --partition-type data --partition-subtype ota --partition-table-file $(PARTITION_TABLE_BIN) \
                                                                -q generate_blank_partition_file --output $(BLANK_OTA_DATA_FILE); \
                        fi; )
-       $(eval BLANK_OTA_DATA_FILE = $(shell if [ $(OTA_DATA_OFFSET) != "" ] && [ $(OTA_DATA_SIZE) != "" ]; then \
+       $(eval BLANK_OTA_DATA_FILE = $(shell if [ "$(OTA_DATA_OFFSET)" != "" ] && [ "$(OTA_DATA_SIZE)" != "" ]; then \
                        echo $(BLANK_OTA_DATA_FILE); else echo " "; fi) )
 
 blank_ota_data: $(BLANK_OTA_DATA_FILE)