The keyword here is 'twice' to explain the trick.
Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
---
usr/include/Makefile | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/usr/include/Makefile b/usr/include/Makefile
index a339ef325aa5..b568a95d1f62 100644
--- a/usr/include/Makefile
+++ b/usr/include/Makefile
@@ -93,7 +93,7 @@ no-header-test += asm-generic/%
extra-y := $(patsubst $(obj)/%.h,%.hdrtest, $(shell find $(obj) -name '*.h' 2>/dev/null))
-# Include the header to detect missing include guard.
+# Include the header twice to detect missing include guard.
quiet_cmd_hdrtest = HDRTEST $<
cmd_hdrtest = \
$(CC) $(c_flags) -S -o /dev/null -x c /dev/null \
--
2.17.1
