Re: [dpdk-dev] [PATCH v2 01/10] build: add an option to enable LTO build

[Ray Kinsella <mdr@ashroe.eu>]

On 19/09/2019 16:16, Bruce Richardson wrote:
> On Thu, Sep 19, 2019 at 02:28:04PM +0100, Ray Kinsella wrote:
>>
>>
>> On 19/09/2019 13:35, Andrzej Ostruszka wrote:
>>> On 9/18/19 3:32 PM, Ray Kinsella wrote:
>> ...>
>>> Compilation time is much longer.  In a normal hack|fix/compile/repeat
>>> cycle with "compile" part being simple "make" the link time might be a
>>> bit annoying.  So I imagine keeping LTO off for the most part of the dev
>>> cycle and then at the end when doing release/cleanup turn LTO on - to
>>> either get release build ready or to get some set of warnings that you
>>> address before yet another attempt to release build.  
>>
>> Well look, I would say a few things.
>>
>> 1. I see build times going down dramatically with Meson/Ninja in any case.
> 
> In the general case yes, but mainly it helps if you have a large number of
> cores. For anyone building in a CI with only a couple of cores, meson+ninja
> isn't going to help much.
> 
> /Bruce
> 

Very true, and I completely acknowledge that LTO adds compilation time.
I would just like to see it in or out, not another build time option.

Ray K