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From: kilgallen@eisner.decus.org (Larry Kilgallen)
Subject: Re: Waiver question
Date: 1997/05/02
Message-ID: <1997May2.063334.1@eisner>#1/1
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References: <dewar.861594356@merv> <5k52k2$7v0$1@news.nyu.edu>
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Date: 1997-05-02T00:00:00+00:00
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In article <E9J2rB.G04@world.std.com>, bobduff@world.std.com (Robert A Duff) writes:

> Strange semantics, IMHO.  Pragma Pack is all about time-vs-space
> trade-offs, but it has this weird side-effect on tasking semantics.  We
> should have a way to *declare* things independently adressable, but the
> default should be that things are not.

I do not understand why you feel the default should be task-unsafe.
The general trend in Ada seems to be that safeguards are enabled by
default and disabled by explicit statement.

In addition to multiprocessing considerations, there are also
efficiency reasons for having the compiler put each variable
into a separate Alpha longword (or set thereof).

The only wasted resource is memory, and typical applications on
Alpha have lots.  Others can declare their preference for the
task-unsafe version on particular constructs.

Certainly defaulting to task-safe seems to be a lot more friendly
for those porting programs in from other platforms.

Larry Kilgallen