Re: [Qemu-devel] [PATCH for-2.4] acpi: avoid potential uninitialized access to cpu_hp_io_base

[Igor Mammedov <imammedo@redhat.com>]

On Fri, 31 Jul 2015 11:14:35 +0100
"Daniel P. Berrange" <berrange@redhat.com> wrote:

> When building QEMU with Mingw64 toolchain I see a warning
> 
>  CC    x86_64-softmmu/hw/i386/acpi-build.o
>   hw/i386/acpi-build.c: In function 'acpi_build':
>   hw/i386/acpi-build.c:1138:9: warning: 'pm.cpu_hp_io_base' may be used uninitialized in this function [-Wmaybe-uninitialized]
>            aml_append(crs,
>            ^
>   hw/i386/acpi-build.c:1666:16: note: 'pm.cpu_hp_io_base' was declared here
>        AcpiPmInfo pm;
>                   ^
> 
> In acpi_get_pm_info() some of the fields are pre-initialized
> to 0, but this one was missed.
> 
> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Impossible in practice since piix or lpc branches will initialize it,
but there is no harm in making compiler happy.

Reviewed-by: Igor Mammedov <imammedo@redhat.com>

> ---
>  hw/i386/acpi-build.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> index 46eddb8..95e0c65 100644
> --- a/hw/i386/acpi-build.c
> +++ b/hw/i386/acpi-build.c
> @@ -169,6 +169,7 @@ static void acpi_get_pm_info(AcpiPmInfo *pm)
>      Object *obj = NULL;
>      QObject *o;
>  
> +    pm->cpu_hp_io_base = 0;
>      pm->pcihp_io_base = 0;
>      pm->pcihp_io_len = 0;
>      if (piix) {