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    SubjectRe: List of all-zero .data variables in linux-2.4.3 available
    >> = Adam Richter
    > = Ulrich Drepper

    >> >Shouldn't a compiler be able to deal with this instead?
    >>
    >> Yes.

    >No. gcc must not do this. There are situations where you must place
    >a zero-initialized variable in .data. It is a programmer problem.

    I am aware of a couple of cases where code relied on static
    variables being allocated contiguously, but, in both cases, those
    variables were either all zeros or all non-zeros, so my proposed
    change would not break such code. Also, variables being allocated
    contiguously is not an assumption supported by any standard that
    I am aware of, and the very rare cases where code relies on this
    should instead use an array (they've been of the same type in the
    examples that I have come across). At the very least, it seems
    to me that this should be a compiler optimization flag, preferably
    defaulted to "on".

    If you have some other scenario in mind, I'd appreciate an
    example or a clear reference to some explanation, and I think others
    on linux-kernel would probably appreciate that too. It is a topic
    that comes up repeatedly on linux-kernel.

    Adam J. Richter __ ______________ 4880 Stevens Creek Blvd, Suite 104
    adam@yggdrasil.com \ / San Jose, California 95129-1034
    +1 408 261-6630 | g g d r a s i l United States of America
    fax +1 408 261-6631 "Free Software For The Rest Of Us."
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