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From: bobduff@world.std.com (Robert A Duff)
Subject: Re: access aliased obstacle
Date: 1996/07/10
Message-ID: <DuBxBE.Hoq@world.std.com>#1/1
X-Deja-AN: 167572990
references: <4rsmn6$hvc@news1.delphi.com> <dewar.836941369@schonberg>
 <ws920ilyp94.fsf@schonberg.cs.nyu.edu> <dewar.836958957@schonberg>
organization: The World Public Access UNIX, Brookline, MA
newsgroups: comp.lang.ada
Date: 1996-07-10T00:00:00+00:00
List-Id: <comp.lang.ada>


In article <dewar.836958957@schonberg>, Robert Dewar <dewar@cs.nyu.edu> wrote:
[stuff about storing discriminants separately]

If you do that, then in some cases, you can avoid storing the
discriminants altogether.  If you have a variable
X: T(Discrim => static-expression), then there's no need to store
X.Discrim anywhere.  Of course if X is ever passed to an unconstrained
formal parameter, the discriminant value has to be materialized at that
point.  And aliased variables need to have discriminants attached to
them, or accessible in some way.

Discriminants are really quite similar to array bounds.

- Bob