Commit b5960a06 authored by Nathan Chancellor's avatar Nathan Chancellor Committed by Petr Mladek
Browse files

vsprintf: Use __diag macros to disable '-Wsuggest-attribute=format' 

The GCC specific warning '-Wsuggest-attribute=format' is disabled around
va_format() using raw #pragma statements, which includes an
'#ifndef __clang__' to avoid a warning about an unknown warning option
from clang (which recognizes '#pragma GCC' for compatibility reasons):

  lib/vsprintf.c:1703:32: error: unknown warning group '-Wsuggest-attribute=format', ignored [-Werror,-Wunknown-warning-option]
   1703 | #pragma GCC diagnostic ignored "-Wsuggest-attribute=format"
        |                                ^

While the current solution works, it is not visually appealing. The
kernel already has some infrastructure that wraps these #pragma
statements to give more specific control over diagnostics without
needing #ifdef blocks for different compilers. Convert the existing
statements over to the __diag macros.

Closes: https://lore.kernel.org/r/CAHk-=wgfX9nBGE0Ap9GjhOy7Mn=RSy=rx0MvqfYFFDx31KJXqQ@mail.gmail.com


Signed-off-by: default avatarNathan Chancellor <nathan@kernel.org>
Tested-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: default avatarPetr Mladek <pmladek@suse.com>
Link: https://patch.msgid.link/20250404-vsprintf-convert-pragmas-to-__diag-v1-2-5d6c5c55b2bd@kernel.org


Signed-off-by: default avatarPetr Mladek <pmladek@suse.com>
parent 7efa84b5

lib/vsprintf.c

+4 −5
Original line number Diff line number Diff line
@@ -1699,10 +1699,9 @@ char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 
	return buf;

}



#pragma GCC diagnostic push

#ifndef __clang__

#pragma GCC diagnostic ignored "-Wsuggest-attribute=format"

#endif

__diag_push();

__diag_ignore(GCC, all, "-Wsuggest-attribute=format",

	      "Not a valid __printf() conversion candidate.");

static char *va_format(char *buf, char *end, struct va_format *va_fmt,

		       struct printf_spec spec)

{
@@ -1717,7 +1716,7 @@ static char *va_format(char *buf, char *end, struct va_format *va_fmt, 


	return buf;

}

#pragma GCC diagnostic pop

__diag_pop();



static noinline_for_stack

char *uuid_string(char *buf, char *end, const u8 *addr,