New primitive types?

Florian Weimer fw at
Sat Aug 19 08:34:56 UTC 2017

* Michal Terepeta:

> On Tue, Aug 1, 2017 at 8:08 PM Carter Schonwald <carter.schonwald at>
> wrote:
>> One issue with packed fields is that on many architectures you can't
> quite do subword reads or
>> writes.  So it might not always be a win.
> Could you give any examples?

Historic DEC Alpha, now long obsolete.

It is very hard to create compliant and performant implementations of
Java 5, C 11 or C++ 11 on such architectures.  All these languages
(and their subsequent revisions) require that naturally aligned
objects can be accessed independently.  For example, you can't use a
simple read-modify-write cycle to implement a single-byte store using
word operations.

That's why such architectures really do not have a future (or even a
present), except maybe in niche markets such as GPGPU (but even there,
things are heading towards the de-facto standard memory model).

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