[PULL 41/41] tests/rcutorture: Fix build error

Cédric Le Goater posted 41 patches 3 weeks, 6 days ago
Maintainers: Yi Liu <yi.l.liu@intel.com>, Eric Auger <eric.auger@redhat.com>, Zhenzhong Duan <zhenzhong.duan@intel.com>, Paolo Bonzini <pbonzini@redhat.com>, Richard Henderson <richard.henderson@linaro.org>, Eduardo Habkost <eduardo@habkost.net>, "Michael S. Tsirkin" <mst@redhat.com>, Marcel Apfelbaum <marcel.apfelbaum@gmail.com>, Jason Wang <jasowang@redhat.com>, "Clément Mathieu--Drif" <clement.mathieu--drif@eviden.com>, Alexey Kardashevskiy <aik@ozlabs.ru>, John Levon <john.levon@nutanix.com>, Thanos Makatos <thanos.makatos@nutanix.com>, "Cédric Le Goater" <clg@redhat.com>, Alex Williamson <alex@shazbot.org>, Magnus Kulke <magnus.kulke@linux.microsoft.com>, Wei Liu <wei.liu@kernel.org>, Cornelia Huck <cohuck@redhat.com>, Palmer Dabbelt <palmer@dabbelt.com>, Alistair Francis <alistair.francis@wdc.com>, Weiwei Li <liwei1518@gmail.com>, Daniel Henrique Barboza <dbarboza@ventanamicro.com>, Liu Zhiwei <zhiwei_liu@linux.alibaba.com>, Fabiano Rosas <farosas@suse.de>, Laurent Vivier <lvivier@redhat.com>
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[PULL 41/41] tests/rcutorture: Fix build error
Posted by Cédric Le Goater 3 weeks, 6 days ago
Newer gcc compiler (version 16.0.0 20260103 (Red Hat 16.0.0-0) (GCC))
detects an unused variable error:

  ../tests/unit/rcutorture.c: In function ‘rcu_read_stress_test’:
  ../tests/unit/rcutorture.c:251:18: error: variable ‘garbage’ set but not used [-Werror=unused-but-set-variable=]
    251 |     volatile int garbage = 0;
        |                  ^~~~~~~

Since the 'garbage' variable is used to generate memory reads from the
CPU while holding the RCU lock, it can not be removed. Tag it as
((unused)) instead to silence the compiler warnings/errors.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Link: https://lore.kernel.org/qemu-devel/20260112163350.1251114-1-clg@redhat.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>
---
 tests/unit/rcutorture.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/unit/rcutorture.c b/tests/unit/rcutorture.c
index 7662081683f5d781da74402113b73884780b1243..2f19d479a3f210cbca19205a0656eda1f4c2e5a7 100644
--- a/tests/unit/rcutorture.c
+++ b/tests/unit/rcutorture.c
@@ -248,7 +248,7 @@ static void *rcu_read_stress_test(void *arg)
     int pc;
     long long n_reads_local = 0;
     long long rcu_stress_local[RCU_STRESS_PIPE_LEN + 1] = { 0 };
-    volatile int garbage = 0;
+    volatile int garbage __attribute__ ((unused)) = 0;
 
     rcu_register_thread();
 
-- 
2.52.0