From 9bfa52dac27a20b43bcb73e56dc45aba6b9aaff1 Mon Sep 17 00:00:00 2001 From: Tamir Duberstein Date: Wed, 21 Jan 2026 11:10:08 -0500 Subject: [PATCH] printf: convert test_hashed into macro This allows the compiler to check the arguments against the __printf() attribute on __test(). This produces better diagnostics when incorrect inputs are passed. Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202512061600.89CKQ3ag-lkp@intel.com/ Signed-off-by: Tamir Duberstein Reviewed-by: Petr Mladek Reviewed-by: Andy Shevchenko Link: https://patch.msgid.link/20260121-printf-kunit-printf-attr-v3-1-4144f337ec8b@kernel.org Signed-off-by: Petr Mladek --- lib/tests/printf_kunit.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/lib/tests/printf_kunit.c b/lib/tests/printf_kunit.c index 7617e5b8b02cc..f6f21b445ece1 100644 --- a/lib/tests/printf_kunit.c +++ b/lib/tests/printf_kunit.c @@ -266,15 +266,17 @@ hash_pointer(struct kunit *kunittest) KUNIT_EXPECT_MEMNEQ(kunittest, buf, PTR_STR, PTR_WIDTH); } -static void -test_hashed(struct kunit *kunittest, const char *fmt, const void *p) -{ - char buf[PLAIN_BUF_SIZE]; - - plain_hash_to_buffer(kunittest, p, buf, PLAIN_BUF_SIZE); - - test(buf, fmt, p); -} +/* + * This is a macro so that the compiler can compare its arguments to the + * __printf() attribute on __test(). This cannot be a function with a __printf() + * attribute because GCC requires __printf() functions to be variadic. + */ +#define test_hashed(kunittest, fmt, p) \ + do { \ + char buf[PLAIN_BUF_SIZE]; \ + plain_hash_to_buffer(kunittest, p, buf, PLAIN_BUF_SIZE); \ + test(buf, fmt, p); \ + } while (0) /* * NULL pointers aren't hashed. -- 2.47.3