Re: [PATCH v2 18/18] arm64: select ARCH_SUPPORTS_LTO_CLANG

From: Paul E. McKenney
Date: Mon Nov 20 2017 - 15:54:01 EST

On Mon, Nov 20, 2017 at 08:32:56PM +0100, Peter Zijlstra wrote:
> On Mon, Nov 20, 2017 at 06:05:55PM +0000, Will Deacon wrote:
> > Although the current direction of the C++ committee is to prefer
> > that dependencies are explicitly "marked", this is not deemed to be
> > acceptable for the kernel (in other words, everything is always considered
> > "marked").
> Yeah, that is an attitude not compatible with existing code. Much like
> the proposal to allow temporary/wide stores on everything not explicitly
> declared atomic. Such stuff instantly breaks all extant code that does
> multi-threading with no recourse.

If someone suggests temporary/wide stores, even on non-atomics, tell
them that the standard does not permit them to introduce data races.

Thanx, Paul