Re: errata/650: 9.7.6 does not explicitly say what happens if "wait" condition is x or z

From: Shalom.Bresticker@freescale.com
Date: Tue Feb 15 2005 - 18:40:00 PST

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    The following reply was made to PR errata/650; it has been noted by GNATS.

    From: Shalom.Bresticker@freescale.com
    To: Steven Sharp <sharp@cadence.com>
    Cc: etf-bugs@boyd.com
    Subject: Re: errata/650: 9.7.6 does not explicitly say what happens if "wait"
     condition is x or z
    Date: Wed, 16 Feb 2005 04:56:53 +0200 (IST)

     Yes to all you wrote.
     
     By chance, I am reviewing Clause 14 (Specify blocks) due to some specify
     syntax which appears to be accepted by most of the simulators, but is
     not allowed by the BNF. (Expect an errata on it in the near future.)
     
     14.2.4.1 says, "If the conditional expression evaluates to x or z, it shall
     be treated as true." Again, in context that is probably the correct behavior,
     but it is different than elsewhere.
     
     Shalom
     
     
     On Tue, 15 Feb 2005, Steven Sharp wrote:
     
    >
    > > I agree that this was the intent. However, the terms true and false are almost
    > > certainly used in other contexts where x and z are not included. So it would
    > > be more precise to say that x is considered false in the context of a
    > > condition, not an arbitrary expression.
    > >
    > > And even there, there are exceptions. Remember issue 237?
    >
    > For that issue, the text in 15.6 clearly states how x is treated, and
    > does not use the terms true and false. The correctness of the text is
    > questionable, but it does not appear to conflict with the definitions
    > of true and false.
    >
    > The conditional operator also describes how x is treated. However, it
    > uses the terms true and false, and defines them differently from the
    > definition for "if" statements. This could create confusion.
    >
    >
    > > Further, if someone looks up what is written in 9.6 or 9.7.6, there is no
    > > reason he should think that 9.4 is relevant.
    >
    > I agree that the organization is poor. It may work for someone reading
    > the text from front to back, but not for someone looking something up.
    > It could be specified better by repeating the definition every place it
    > is used, or by moving the definition into a separate section and stating
    > that it apples to all conditions in procedural statements.
    >
    > Steven Sharp
    > sharp@cadence.com
    >
     
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     Shalom Bresticker Shalom.Bresticker @freescale.com
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