Re: [PATCH] tools/build: tweak unused value workaround

[George Burgess]

On Tue, Apr 14, 2020 at 5:00 PM Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote:
> What does "disabled by default" mean?  Presumably it should now be
> enabled, but I don't think this disabling happens in the mainline
> kernel tree?

Disabled when `perf` does its configure-ish checks. Concretely,

```
~/linux/tools/perf $ make V=1 VF=1 CC=$clang -f Makefile.perf notarget \
    |& grep 'Auto-detecting\|sync-compare-and-swap'
Auto-detecting system features:
...         sync-compare-and-swap: [ OFF ]
```