[PATCH v3 1/8] tests: Allow tests to append tunables

[Yury Khrustalev]

On Tue, Apr 21, 2026 at 10:08:16AM -0300, Adhemerval Zanella Netto wrote:
> 
> On 16/04/26 11:30, Yury Khrustalev wrote:
> > Many tests use Glibc tunables, and the values of the tunables are
> > provided via the GLIBC_TUNABLES env variable. Tests set it in
> > makefiles using
> > 
> >   tst-foo-ENV = GLIBC_TUNABLES=tunable=value
> >
> > ...
> >
> > Additionally, we support cases when tests must have specific value
> > of the GLIBC_TUNABLES env var (ignoring any ambient value):
> > 
> >   tst-foo-TUNABLES-only += tunable=value
> > 
> > The existing mechanism that uses tst-foo-ENV will continue to work,
> > however if the same test uses both, the new mechanism will override
> > the old one.
> > 
> > Additional benefit is that the code in makefiles becomes shorter.
> > 
> > We also change tunable handling for malloc tests in this commit.
> 
> Thanks, I like this approach better than the previous one.
> 
> Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

Thank you for the review. I've posted v4 [1] with very small changes:

 - Fixed grammar as per your comment below.
 - Fixed $(subst $(empty) ,:,$(strip $(FOO)))' based on Andreas'
   comments.
 - Fixed 4 GCS audit tests and 1 BTI test in the last commit in the
   series that would fail when ambient GLIBC_TUNABLES variable is
   used with the aarch64_gcs tunable.

>
> ...
> > +# Generate environment variable GLIBC_TUNABLES to be appended to
> > +# the test environment appending tunables specifically added for
> 
> Maybe add a comma after 'environment' here.  The resto look ok.
> 

[1]: https://inbox.sourceware.org/libc-alpha/20260421143804.3933020-1-yury.khrustalev@arm.com

Thanks,
Yury