Profile Guided Optimization (PGO)

[Orians, Jeremiah (DTMB)]

>> It'll solve the reproducible problem but introduce a bootstrapping 
>> problem for how those files were generated in the first place.
>FWIW, this seems sorta fine to me.
>As long as a build path exists which _doesn't_ require the PGO AOT snapshot info to build successfully.
That is very true, however we have seen even GNU packages that couldn't be built from the distributed
source code and everyone just used the "pregenerated" files to produce working binaries.

So I have very little trust that builds without such crap will continue to work correctly.

> But that seems unlikely to rot, doesn't it?
Any functionality or path not routinely exercised on *EVERY* release has a tendency to decay until it no
longer functions. Much like inactive genes accumulate mutations with each passing generation.

And if GNU packages can't even preserve the ability to be built from source code, what gives you faith that
these optimizations wouldn't bring similar problems going forward?

-Jeremiah