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charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 6 Jun 2024, at 7:35, Matthew Wilcox wrote: > On Thu, Jun 06, 2024 at 01:58:35PM +0000, Pankaj Raghav (Samsung) wrote= : >> +++ b/tools/testing/selftests/mm/split_huge_page_test.c >> @@ -300,7 +300,7 @@ int create_pagecache_thp_and_fd(const char *testfi= le, size_t fd_size, int *fd, >> char **addr) >> { >> size_t i; >> - int __attribute__((unused)) dummy =3D 0; >> + volatile int __attribute__((unused)) dummy =3D 0; > > The mistake made by whoever wrote this test was making 'dummy' a stack That was me. :( > variable. That lets the compiler figure out that it's unused. If you > make it a top-level variable (not static) so the compiler can't tell > whether it's referenced by a different compilation unit, it can't make > that deduction. And you don't need the stupid attibute or volatile on = it. It is better to just move =E2=80=9Cdummy=E2=80=9D like you suggested inst= ead of adding more keywords to fix it. - Best Regards, Yan, Zi --=_MailMate_5634B141-D808-4ACD-A931-0E5C48B7F427_= Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename=signature.asc Content-Type: application/pgp-signature; name=signature.asc -----BEGIN PGP SIGNATURE----- iQJDBAEBCgAtFiEEh7yFAW3gwjwQ4C9anbJR82th+ooFAmZh03MPHHppeUBudmlk aWEuY29tAAoJEJ2yUfNrYfqKmgMQAIn7gOvl6o9OPu/3Afyon/ao1gQUrZbrXRpO TMnNsKI7GxNBgTQ3sx54DGRBOARi5W1RFdJxY1psQfO+0wZ5+SP6fnypwubEJfwi HJAjwk/vZFwtra4sHaOiv5Ir6LMMgrciiwHJYmaAPwa7Gk5lOW4nIFA5Fy4RMZor 0vFsq/Siu2DJloh+uRxDmNosJy/go2KRGZRubiTzDwpF3q3qmKrUgiohVFYQVjPK DSUGHQZ7Ky2XzbrYRz89uLFLvy+E2X4U7AvgdE6cfPhjfozdkr3bQAicG+Jl/BDD hfzmT2GOTwQHgBW3d9jVnFphMxaq4j7yEWdE+VY3oq/TQrUkYSD+aNXdBzQ5s7Ff 8f/5PIl50MVrfeaEOG+//fe192SXBUvH6sfV5tIXqEOd4JY+8q4fS9umqPqfojZ6 puSTnHawC77dgV7DWi4b+ZDwDVviwmmS4b0utlcEjPu0Ium+6GaltQYCUxwxivyD falHMetTu3LHdnpVa2Wn0/xDstuaqAoqQa5yhUeYnHa7XfDvS3Smqb2qwAsWiZmb fGPIDkrqSAdmfxp+W2xnbRd7gbMgaF/2bhXS+0c+rIuYe5b5rt4eIlgaV519Wo5H f2436k9QUMI9jeFG16zhpJyKS7ErRS9+ZjTpoZW1wfSj8ihVXCvgOrPHtnF9OHUX 3DP24VJY =2dvt -----END PGP SIGNATURE----- --=_MailMate_5634B141-D808-4ACD-A931-0E5C48B7F427_=--