Re: [boost] Build breaking changes

On 03/29/18 05:51, Vinnie Falco via Boost wrote:

On Wed, Mar 28, 2018 at 5:49 PM, Andrey Semashev via Boost wrote:

...

If someone wants to target an outdated architecture (and 32-bit x86 really is a separate architecture, including hardware features and software ABI) then let them do that with a little more effort. The rest of the world have moved to 64 bits long ago, and that is what we should target by default, IMO.

No they have not all "moved on to 64 bits." Most programs work perfectly fine as 32-bit applications and have no need for the ability to access a full 64-bit address space. In fact many programs perform objectively worse as 64-bit application since pointers and data structures become larger without a corresponding benefit. This is especially true for mobile applications.

Memory is cheap and the increase from the pointer size is not significant[1]. Although x86 is not really relevant in that area, even mainstream smartphones now have 3+ GiB of RAM. Laptops come with more than 4. The x32[2] initiative didn't really take off[3] because the benefits from reducing pointers to 32 bits are not significant enough. I really don't understand why people cling to the old x86 while the bits of silicon and associated performance lie wasted in their CPUs. [1]: https://youtu.be/nLOXwRhOhWY?t=410 - before that time there are performance comparisons [2]: https://en.wikipedia.org/wiki/X32_ABI [3]: https://www.phoronix.com/scan.php?page=news_item&px=MTU1MjE