diff --git a/core/config.mk b/core/config.mk
index e24e957..de0a06b 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -753,13 +753,16 @@
 endif
 .KATI_READONLY := BOARD_CURRENT_API_LEVEL_FOR_VENDOR_MODULES
 
-min_systemsdk_version := $(firstword $(BOARD_API_LEVEL) $(BOARD_SHIPPING_API_LEVEL) $(PRODUCT_SHIPPING_API_LEVEL))
-ifneq (,$(min_systemsdk_version))
-ifneq ($(call numbers_less_than,$(min_systemsdk_version),$(BOARD_SYSTEMSDK_VERSIONS)),)
-  $(error BOARD_SYSTEMSDK_VERSIONS ($(BOARD_SYSTEMSDK_VERSIONS)) must all be greater than or equal to BOARD_API_LEVEL, BOARD_SHIPPING_API_LEVEL or PRODUCT_SHIPPING_API_LEVEL ($(min_systemsdk_version)))
-endif
-endif
 ifdef PRODUCT_SHIPPING_API_LEVEL
+  board_api_level := $(firstword $(BOARD_API_LEVEL) $(BOARD_SHIPPING_API_LEVEL))
+  ifneq (,$(board_api_level))
+    min_systemsdk_version := $(call math_min,$(board_api_level),$(PRODUCT_SHIPPING_API_LEVEL))
+  else
+    min_systemsdk_version := $(PRODUCT_SHIPPING_API_LEVEL)
+  endif
+  ifneq ($(call numbers_less_than,$(min_systemsdk_version),$(BOARD_SYSTEMSDK_VERSIONS)),)
+    $(error BOARD_SYSTEMSDK_VERSIONS ($(BOARD_SYSTEMSDK_VERSIONS)) must all be greater than or equal to BOARD_API_LEVEL, BOARD_SHIPPING_API_LEVEL or PRODUCT_SHIPPING_API_LEVEL ($(min_systemsdk_version)))
+  endif
   ifneq ($(call math_gt_or_eq,$(PRODUCT_SHIPPING_API_LEVEL),28),)
     ifneq ($(TARGET_IS_64_BIT), true)
       ifneq ($(TARGET_USES_64_BIT_BINDER), true)