When compiling with GCC 10 (Fedora 32) using CFLAGS=-O2 we get: CC or1k-softmmu/hw/openrisc/openrisc_sim.o hw/openrisc/openrisc_sim.c: In function ‘openrisc_sim_init’: hw/openrisc/openrisc_sim.c:87:42: error: ‘cpu_irqs[0]’ may be used uninitialized in this function [-Werror=maybe-uninitialized] 87 | sysbus_connect_irq(s, i, cpu_irqs[i][irq_pin]); | ~~~~~~~~^~~
While humans can tell smp_cpus will always be in the [1, 2] range, (openrisc_sim_machine_init sets mc->max_cpus = 2), the compiler can't. Add an assertion to give the compiler a hint there's no use of uninitialized data. Buglink: https://bugs.launchpad.net/qemu/+bug/1874073 Reported-by: Martin Liška <mli...@suse.cz> Suggested-by: Peter Maydell <peter.mayd...@linaro.org> Signed-off-by: Philippe Mathieu-Daudé <phi...@redhat.com> --- hw/openrisc/openrisc_sim.c | 1 + 1 file changed, 1 insertion(+) diff --git a/hw/openrisc/openrisc_sim.c b/hw/openrisc/openrisc_sim.c index d08ce61811..02f5259e5e 100644 --- a/hw/openrisc/openrisc_sim.c +++ b/hw/openrisc/openrisc_sim.c @@ -134,6 +134,7 @@ static void openrisc_sim_init(MachineState *machine) int n; unsigned int smp_cpus = machine->smp.cpus; + assert(smp_cpus >= 1 && smp_cpus <= 2); for (n = 0; n < smp_cpus; n++) { cpu = OPENRISC_CPU(cpu_create(machine->cpu_type)); if (cpu == NULL) { -- 2.21.3