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    SubjectRe: kfree(0) - ok?

    On Aug 15 2007 09:58, Kyle Moffett wrote:
    >
    > Irrespective of whatever the standard says, EVERY platform and
    > compiler anybody makes nowadays has a NULL pointer value with all
    > bits clear. Theoretically the standard allows otherwise, but such
    > a decision would break so much code. Linux especially, we rely on
    > the uninitialized data to have all bits clear and we depend on that
    > producing NULL pointers; if a NULL pointer was not bitwise exactly
    > 0 then the test "if (some_ptr != NULL)" would fail and we would
    > start dereferencing garbage.

    But if kmalloc returns NULL on failure, then testing for NULL
    (irrespective of being 0 or 0xDEADBEEF) is ok.
    What would actually concern me then is what "if (!some_ptr)" would do.
    Probably not the right thing.


    Jan
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