Re: [boost] [Review] Boost.Endian mini-review

Subject: Re: [boost] [Review] Boost.Endian mini-review
From: Olaf van der Spek (ml_at_[hidden])
Date: 2015-01-24 11:13:27

On Sat, Jan 24, 2015 at 5:04 PM, Peter Dimov <lists_at_[hidden]> wrote:
> Olaf van der Spek wrote:
>>
>> On Sat, Jan 24, 2015 at 3:54 PM, Beman Dawes <bdawes_at_[hidden]> wrote:
>> >    struct
>> >    {
>> >        big_int32_buf_t code;
>> >        big_uint32_buf_t length;
>> >        little_int16_buf_t version;
>> >        big_int32_buf_ut shape_type;
>> >    } data;
>>
>> You're mixing aligned and unaligned types. Shouldn't all be unaligned? See
>> the docs: "Warning: Code that uses aligned types is possibly non-portable
>> because alignment requirements vary between hardware architectures and
>> because alignment may be affected by compiler switches or pragmas. For
>> example, alignment of an 64-bit integer may be to a 32-bit boundary on a
>> 32-bit machine. Furthermore, aligned types are only available on
>> architectures with 16, 32, and 64-bit integer types."
>
>
> Yes, a good argument against having aligned buffers at all, even though the
> docs do provide rationale for them. If you want aligned, use the non-buffer
> types.

I think the default / shortest name types should be unaligned, with
aligned access being explicit.

-- 
Olaf