diff --git a/make/common/MakeIO.gmk b/make/common/MakeIO.gmk
index 7b4dd0a3c88..9d0aee6bbad 100644
--- a/make/common/MakeIO.gmk
+++ b/make/common/MakeIO.gmk
@@ -268,5 +268,5 @@ ifeq ($(HAS_FILE_FUNCTION), true)
 else
   # Use printf to get consistent behavior on all platforms.
   AppendFile = \
-      $(shell $(PRINTF) "%s" $(call ShellQuote, $1) >> $2)
+      $(shell $(PRINTF) "%s\n" $(call ShellQuote, $1) >> $2)
 endif