linux-kernel - [PATCH v1 1/1] lib/vsprintf.c: Amend static asserts for format specifier flags

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Message-Id: <20211026140356.45610-1-andriy.shevchenko@linux.intel.com>
Date:   Tue, 26 Oct 2021 17:03:56 +0300
From:   Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To:     Petr Mladek <pmladek@...e.com>, linux-kernel@...r.kernel.org
Cc:     Steven Rostedt <rostedt@...dmis.org>,
        Sergey Senozhatsky <senozhatsky@...omium.org>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Rasmus Villemoes <linux@...musvillemoes.dk>
Subject: [PATCH v1 1/1] lib/vsprintf.c: Amend static asserts for format specifier flags

There are couple of improvements to static asserts against
the format specifier flags:

- new static assert for SIGN
- fix static assert for SMALL

SMALL is not equal to ASCII code of white space, it equals to
the bit difference between capital and small letters (however
the value is the same, semantically expression means different
things).

Signed-off-by: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
---
 lib/vsprintf.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index f15a49ff6fab..ddfb3d836f38 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -407,8 +407,9 @@ int num_to_str(char *buf, int size, unsigned long long num, unsigned int width)
 #define SMALL	32		/* use lowercase in hex (must be 32 == 0x20) */
 #define SPECIAL	64		/* prefix hex with "0x", octal with "0" */
 
+static_assert(SIGN == 1);
 static_assert(ZEROPAD == ('0' - ' '));
-static_assert(SMALL == ' ');
+static_assert(SMALL == ('a' ^ 'A'));
 
 enum format_type {
 	FORMAT_TYPE_NONE, /* Just a string part */
-- 
2.33.0