Re: Have we become too Intel x64 centered?

From: Edward Diener (eldiener_at_[hidden])
Date: 2021-01-27 04:38:33

On 1/25/2021 6:08 PM, Gavin Lambert via Boost wrote:
> On 26/01/2021 10:53 am, Edward Diener wrote:
>> Please name the Boost low level libraries which have specific code 
>> aimed at the platform/architecture combination. I am not talking about 
>> code for just Mac or Linux or Solaris or Windows but code that 
>> actually does something different when run on Intel or ARM or AArch64 
>> etc. I still imagine that if such Boost libraries exist there are 
>> still very, very few Boost libraries with dependence on such code. I 
>> am not arguing that testing on non-Intel is in any way wrong but 
>> simply that very, very few libraries should be impacted by different 
>> architectures in any way.
> 
> Boost.Atomic (and consequently Boost.Lockfree too) is the obvious one 
> (that Niall already hinted at), but parts of Boost.Thread also apply.
> 
> Add to that list other low-level libraries such as Boost.Endian, 
> Boost.Coroutine[2], and Boost.Fiber as well.
> 
> There are also some surprise gotchas in other libraries that do their 
> own spinlocks or pointer-packing, such as Boost.SmartPtr and likely others.
> 
> Meanwhile other libraries like Boost.Serialization (and consumers of 
> same) also make their own assumptions about things like endianness and 
> type structure, which may not matter too much in isolation but becomes 
> very important if you're intending to use it as a portable network or 
> disk format.

I think then it is important for the libraries in which some of the code 
is tailored to a platform/architecture to test on other 
platform/architectures than Intel, but for the large number of Boost 
libraries which have no direct dependencies on a platform/architecture I 
do not see that it is of much importance. Simply because library XXX 
uses Boost.SmartPtr does not mean that testing on ARM is going to show 
anything of use for library XXX, which testing Boost.SmartPtr on ARM 
would not itself show.