errata/467: assignments on port declarations 12.3

From: sharp@cadence.com
Date: Fri Sep 12 2003 - 14:01:38 PDT

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    >Number: 467
    >Category: errata
    >Originator: sharp@cadence.com
    >Environment:

    >Description:

    This is a question, probably not a real erratum.

    Looking at the BNF, it appears to allow reg declaration
    initializers on reg port declarations, both the combined
    reg port declarations inside the module and the ANSI-C
    style reg port declarations in the port list.

    It does not allow continuous assignments on net declarations
    if those are net port declarations, whether those are
    combined net port declarations inside the module or ANSI-C
    style net port declarations in the port list.

    So the BNF allows both

            module m (output reg r = 0);

    and

            module m (r);
            output reg r = 0;

    But it does not allow either

            module m (output wire w = 0);

    or

            module m (w);
            output wire w = 0;

    even though it allows

            module m (w);
            output w;
            wire w = 0;

    Is this what was intended? I can see some logic to this,
    since you can't really assign much besides constants this
    way (at least in the ANSI-C style port declarations).
    That makes sense for a reg initializer, but is of limited
    use for a continuous assignment.

    I checked the email archives, but couldn't find anything
    related to this.

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