diff --git a/toolchain/toolchain-external/pkg-toolchain-external.mk b/toolchain/toolchain-external/pkg-toolchain-external.mk
index 299b6008aa..c7f4175c9e 100644
--- a/toolchain/toolchain-external/pkg-toolchain-external.mk
+++ b/toolchain/toolchain-external/pkg-toolchain-external.mk
@@ -69,7 +69,12 @@ ifeq ($(BR2_TOOLCHAIN_EXTERNAL_DOWNLOAD),y)
 TOOLCHAIN_EXTERNAL_INSTALL_DIR = $(TOOLCHAIN_EXTERNAL_DOWNLOAD_INSTALL_DIR)
 else
 TOOLCHAIN_EXTERNAL_INSTALL_DIR = $(abspath $(call qstrip,$(BR2_TOOLCHAIN_EXTERNAL_PATH)))
+ifeq ($(BR2_TOOLCHAIN_EXTERNAL)$(BR_BUILDING),yy)
+ifeq ($(TOOLCHAIN_EXTERNAL_INSTALL_DIR),)
+$(error No external toolchain path set, check your BR2_TOOLCHAIN_EXTERNAL_PATH setting)
 endif
+endif
+endif # BR2_TOOLCHAIN_EXTERNAL_DOWNLOAD
 
 ifeq ($(TOOLCHAIN_EXTERNAL_INSTALL_DIR),)
 ifneq ($(TOOLCHAIN_EXTERNAL_PREFIX),)