[PATCH v1] kbuild: Fix CC_CAN_LINK detection

[Mickaël Salaün]

Most samples cannot be build on some environments because they depend
on CC_CAN_LINK, which is set according to the result of
scripts/cc-can-link.sh called by cc_can_link_user.

Because cc-can-link.sh must now build without warning, it may fail
because it is calling printf() with an empty string:

  + cat
  + gcc -m32 -Werror -Wl,--fatal-warnings -x c - -o /dev/null
  <stdin>: In function ‘main’:
  <stdin>:4:9: error: zero-length gnu_printf format string [-Werror=format-zero-length]
  cc1: all warnings being treated as errors

Fix this warning and the samples build by actually printing something.

Cc: Nathan Chancellor <nathan@xxxxxxxxxx>
Cc: Nicolas Schier <nsc@xxxxxxxxxx>
Cc: Thomas Weißschuh <thomas.weissschuh@xxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Fixes: d81d9d389b9b ("kbuild: don't enable CC_CAN_LINK if the dummy program generates warnings")
Signed-off-by: Mickaël Salaün <mic@xxxxxxxxxxx>
---
 scripts/cc-can-link.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/cc-can-link.sh b/scripts/cc-can-link.sh
index e67fd8d7b684..58dc7dd6d556 100755
--- a/scripts/cc-can-link.sh
+++ b/scripts/cc-can-link.sh
@@ -5,7 +5,7 @@ cat << "END" | $@ -Werror -Wl,--fatal-warnings -x c - -o /dev/null >/dev/null 2>
 #include <stdio.h>
 int main(void)
 {
-	printf("");
+	printf("\n");
 	return 0;
 }
 END
-- 
2.53.0