Re: [PATCH] Revert "perf cs-etm: Move definition of 'traceid_list' global variable from header file"

Salvatore Bonaccorso
2020-11-20T13:34:41Z

Hi Andrey,

On Fri, Nov 20, 2020 at 10:54:22AM +0100, Andrey Zhizhikin wrote:
> On Fri, Nov 20, 2020 at 8:39 AM Salvatore Bonaccorso <carnil@debian.org> wrote:
> >
> > This reverts commit 168200b6d6ea0cb5765943ec5da5b8149701f36a upstream.
> > (but only from 4.19.y)
>
> This revert would fail the build of 4.19.y with gcc10, I believe the
> original commit was introduced to address exactly this case. If this
> is intended behavior that 4.19.y is not compiled with newer gcc
> versions - then this revert is OK.

TTBOMK, this would not regress the build for newer gcc (specifically
gcc10) as 4.19.158 is failing perf tool builds there as well (without
the above commit reverted). Just as an example v4.19.y does not have
cff20b3151cc ("perf tests bp_account: Make global variable static")
which is there in v5.6-rc6 to fix build failures with 10.0.1.

But it did regress builds with older gcc's as for instance used in
Debian buster (gcc 8.3.0) since 4.19.152.

Do I possibly miss something? If there is a solution to make it build
with newer GCCs and *not* regress previously working GCC versions then
this is surely the best outcome though.

Regards,
Salvatore