Re: [sv-ec] Name resolution and imports

<forwarding bounced email from Gordon>

-------- Original Message --------

Date: Thu, 31 Aug 2006 20:14:23 -0700 (PDT)
From: "Vreugdenhil, Gordon" <gordon_vreugdenhil@mentor.com>
To: <Neil.Korpusik@Sun.COM>
Cc: "SV_BC List" <sv-bc@server.verilog.org>,
        "SV_EC List" <sv-ec@server.verilog.org>, <sv-ac@server.verilog.org>,
        "Vreugdenhil, Gordon" <gordon_vreugdenhil@mentor.com>


Neil,

This was certainly my reading (and Mentor's position
on the interpretation).  We've explicitly talked about
this kind of thing in committee and in other contexts
without hearing this alternative position from Synopsys
before.  I was very taken aback (shocked) to hear this
position taken by key committee people from Synopsys.
That is why I raised the issue with such urgency.

I am very opposed to hierarchical references to imports,
chained imports, and any other implications of having
imported names be visible to outside reference.  There
are huge issues with name pollution, it corrupts any
view of a package having local and controllable effect,
etc.  Doug has raised other points and there are still
others that cause me to object to this position.

Gord


-----Original Message-----
From: Neil Korpusik [mailto:Neil.Korpusik@Sun.COM]
Sent: Thu 8/31/2006 5:04 PM
To: Vreugdenhil, Gordon
Cc: SV_BC List; SV_EC List; sv-ac@verilog.org
Subject: Re: [sv-ec] Name resolution and imports
=20
Allowing a hierarchical reference to a variable imported into a module
instance seems to be equivalent to allowing a hierarchical reference to =
a
hierarchical reference. I don't believe that we want to allow this.

19.2.1 says the following

"The import statement provides direct visibility of identifiers within =
packages.
It allows identifiers declared within packages to be visible within the =
current
scope without a package name qualifier."

Doesn't this limit the visibility to the "current scope"? Anything =
declared
in the package isn't part of the scope it is imported into. It's just =
visible
to the importing scope, it isn't part of that scope.



Neil


Gordon Vreugdenhil wrote On 08/31/06 10:03,:
> All,
>=20
> The name resolution working group has encountered an issue that
> needs to be resolved at the committee level.  The issue is directly
> addressed by Mantis 1323 -- "are imported names visible to
> hierarchical references".  Mentor and Cadence have both taken
> the position that they are not; Synopsys has taken the position
> that they are.  This needs to be resolved quickly as implementations
> have (and will continue) to diverge.  This also impacts the issue
> of chained imports (is a symbol imported into a package available
> for import) which is also addressed by Mantis 1323.
>=20
> This issue has a direct bearing on back-annotation, pli, and
> related issues since it impacts what the system must present
> as members of a scope and whether hierarchical names for items
> in a design are unique or not.
>=20
> Currently Mantis 1323 is listed as a BC issue.  I'd like to have
> this issue be resolved asap due to the overall impact of the
> interpretation differences.
>=20
> Question:  should this immediately be elevated to the champions
> level or is it appropriate to leave for SV-BC?
>=20
> Independent of that decision, it would be worthwhile for people
> to speak to this from various perspectives so that we can
> make an informed decision.
>=20
> Gord