diff --git a/make/project_config.mk b/make/project_config.mk
index 79a6efd01..0046c44fb 100644
--- a/make/project_config.mk
+++ b/make/project_config.mk
@@ -4,7 +4,7 @@
 COMPONENT_KCONFIGS := $(foreach component,$(COMPONENT_PATHS),$(wildcard $(component)/Kconfig))
 COMPONENT_KCONFIGS_PROJBUILD := $(foreach component,$(COMPONENT_PATHS),$(wildcard $(component)/Kconfig.projbuild))
 
-ifdef MSYSTEM
+ifeq ($(OS),Windows_NT)
 # kconfiglib requires Windows-style paths for kconfig files
 COMPONENT_KCONFIGS := $(shell cygpath -w $(COMPONENT_KCONFIGS))
 COMPONENT_KCONFIGS_PROJBUILD := $(shell cygpath -w $(COMPONENT_KCONFIGS_PROJBUILD))