Re: [PATCH v2] hw/block: nvme: Fix a build error in nvme_get_feature()

[Peter Maydell]

On Wed, 10 Feb 2021 at 10:23, Bin Meng <bmeng.cn@gmail.com> wrote:
>
> From: Bin Meng <bin.meng@windriver.com>
>
> Current QEMU HEAD nvme.c does not compile:
>
>   hw/block/nvme.c:3242:9: error: ‘result’ may be used uninitialized in this 
> function [-Werror=maybe-uninitialized]
>          trace_pci_nvme_getfeat_vwcache(result ? "enabled" : "disabled");
>          ^
>   hw/block/nvme.c:3150:14: note: ‘result’ was declared here
>      uint32_t result;
>               ^
>
> Explicitly initialize the result to fix it.
>
> Fixes: aa5e55e3b07e ("hw/block/nvme: open code for volatile write cache")
> Signed-off-by: Bin Meng <bin.meng@windriver.com>
>
> ---
>
> Changes in v2:
> - update function name in the commit message
>
>  hw/block/nvme.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/hw/block/nvme.c b/hw/block/nvme.c
> index 5ce21b7..c122ac0 100644
> --- a/hw/block/nvme.c
> +++ b/hw/block/nvme.c
> @@ -3228,6 +3228,7 @@ static uint16_t nvme_get_feature(NvmeCtrl *n, 
> NvmeRequest *req)
>          result = ns->features.err_rec;
>          goto out;
>      case NVME_VOLATILE_WRITE_CACHE:
> +        result = 0;
>          for (i = 1; i <= n->num_namespaces; i++) {
>              ns = nvme_ns(n, i);
>              if (!ns) {
> --

Also spotted by Coverity: CID 1446371

-- PMM