Re: [PATCH 0/7] ARM: hacks for link-time optimization

[Peter Zijlstra]

On Tue, Feb 20, 2018 at 10:59:47PM +0100, Arnd Bergmann wrote:
> Hi Nico, all,
> 
> I was playing with ARM link-time optimization handling earlier this
> month, and eventually got it to build cleanly with randconfig kernels,
> but ended up with a lot of ugly hacks to actually pull it off.

How are we dealing with the fact that LTO can break RCU in very subtle
and scary ways?

Do we have a compiler guy on board that has given us a compiler switch
that kills that optimization (and thereby guarantees that behaviour for
future compilers etc..) ?

Also see the thread here:

  https://lkml.kernel.org/r/20171116115810.GH9361@xxxxxxx

(and yes, this is a fine example of how lore sucks for reading email)