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    SubjectRe: gcc 4.5.1 / as 2.20.51.0.11 miscompiling drivers/char/i8k.c ?
    On 08/11/2010 11:20, Andi Kleen wrote:

    > An asm with live inputs and outputs should never be optimized
    > way. If 4.5.1 started doing that it's seriously broken.

    I don't see that. Consider:

    void foo (void)
    {
    int x, y, z;
    x = 23;
    y = x + 1;
    z = y + 1;
    }

    So far, you'd agree the compiler may optimise the entire function away? So
    why not this:

    void foo (void)
    {
    int x, y, z;
    x = 23;
    asm ("do something" : "=r" (y) : "r" (x) );
    z = y + 1;
    }

    ?

    cheers,
    DaveK


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