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Date: Tue, 1 Oct 2013 21:30:17 +0200
From: Luigi Rizzo <rizzo@iet.unipi.it>
To: freebsd-current@freebsd.org
Subject: CLANG reports an error with %b in printf(9)
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This is on HEAD -- while compiling the kernel with CLANG and slightly
higher warns level, i get errors of this kind (in multiple places):

/usr/home/luigi/FreeBSD/head/sys/cam/cam_xpt.c:1069:27: error: invalid conversion specifier
      'b' [-Werror,-Wformat-invalid-specifier]
                printf("%s%d: quirks=0x%b\n", periph->periph_name,
                                       ~^
/usr/home/luigi/FreeBSD/head/sys/cam/cam_xpt.c:1070:36: error: data argument not used by
      format string [-Werror,-Wformat-extra-args]
                    periph->unit_number, quirks, bit_string);

Does anyone know how hard it is to either disable the warning locally
(for a statement, function or file), or better to teach CLANG that
printf(9) uses two arguments for %b ?

cheers
luigi