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    Subject[PATCH] i8k: Tell gcc that *regs gets clobbered


    More recent GCC caused the i8k driver to stop working, on Slackware
    compiler was upgraded from gcc-4.4.4 to gcc-4.5.1 after which it
    didn't work anymore, meaning the driver didn't load or gave total
    nonsensical output.
    As it turned out the asm(..) statement forgot to mention it modifies
    the *regs variable.
    Credits to Andi Kleen <andi@firstfloor.org> and Andreas Schwab
    <schwab@linux-m68k.org> for providing the fix.

    Signed-off-by: Jim Bos <jim876@xs4all.nl>

    --- linux-2.6.36/drivers/char/i8k.c.ORIG 2010-08-02 17:20:46.000000000 +0200
    +++ linux-2.6.36/drivers/char/i8k.c 2010-11-13 11:35:11.000000000 +0100
    @@ -141,7 +141,7 @@
    "lahf\n\t"
    "shrl $8,%%eax\n\t"
    "andl $1,%%eax\n"
    - :"=a"(rc)
    + :"=a"(rc), "+m" (*regs)
    : "a"(regs)
    : "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
    #else
    @@ -166,7 +166,8 @@
    "movl %%edx,0(%%eax)\n\t"
    "lahf\n\t"
    "shrl $8,%%eax\n\t"
    - "andl $1,%%eax\n":"=a"(rc)
    + "andl $1,%%eax\n"
    + :"=a"(rc), "+m" (*regs)
    : "a"(regs)
    : "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
    #endif
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      Last update: 2010-11-13 12:17    [W:0.020 / U:90.152 seconds]
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