diff --git a/src/Makefile b/src/Makefile
index e5226f95c..9b9aa9ffd 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -1268,7 +1268,7 @@ UNIVERSAL_ENTRY_OBJ  := $(TEMP_DIR)/entry_x86.o
 NET_SENTINEL         := $(TEMP_DIR)/.net-done
 
 # Top-level tracked items in src/ (directories and files)
-TRACKED_TOP := $(shell echo "$(SRCS) $(HEADERS) Makefile incbin" | xargs -n1 | awk -F/ '{print $$1}' | sort -u)
+TRACKED_TOP := $(sort $(foreach f,$(SRCS) $(HEADERS) Makefile incbin,$(firstword $(subst /, ,$(f)))))
 
 # Baseline x86-64 must come first in the final link (Windows --allow-multiple-definition
 # uses the first copy of inline duplicates)