[libvirt] [PATCH 5/5] qemu: Disable errors in qemudShutdownVMDaemon

[Jim Meyering]

Cole Robinson wrote:
> Signed-off-by: Cole Robinson <crobinso at redhat.com>
> ---
>  src/qemu/qemu_driver.c |   10 ++++++++++
>  1 files changed, 10 insertions(+), 0 deletions(-)
>
> diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
> index fc6b9fa..38be88f 100644
> --- a/src/qemu/qemu_driver.c
> +++ b/src/qemu/qemu_driver.c
> @@ -2616,12 +2616,17 @@ static void qemudShutdownVMDaemon(virConnectPtr conn,
>      int ret;
>      int retries = 0;
>      qemuDomainObjPrivatePtr priv = vm->privateData;
> +    virErrorPtr origerr = NULL;

That assignment is technically what they call a dead store,
since the very next use is to overwrite that just-stored value.
So, to avoid warnings from the likes of the clang static checker,
do this instead:

       virErrorPtr origerr;

>      if (!virDomainObjIsActive(vm))
>          return;
>
>      VIR_DEBUG("Shutting down VM '%s'", vm->def->name);
>
> +    /* This method is routinely used in clean up paths. Disable error
> +     * reporting so we don't squash a legit error. */
> +    origerr = virSaveLastError();
> +
>      if (driver->macFilter) {
>          int i;
>          virDomainDefPtr def = vm->def;
> @@ -2701,6 +2706,11 @@ retry:
>          vm->def->id = -1;
>          vm->newDef = NULL;
>      }
> +
> +    if (origerr) {
> +        virSetError(origerr);
> +        virFreeError(origerr);
> +    }
>  }

Hi Cole,
This looks like a fine series.
Is there an easy way to demonstrate the fix?
Thinking it'd be nice to have a test that exercises at least one piece
of the new code.

One tiny comment: people tend not to comprehend
"wordsthatareattachedlikethis".
So if you rename your "origerr" to e.g., "orig_err",
it will be more readable.

If you decide to make the change, you can do it quickly by doing
something like this (assuming the top 5 changes are the ones in this
series, and they've been rebased to the latest master):

  git format-patch --stdout -5 | sed s/origerr/orig_err/ > patch
  git co master
  git co -b var-rename
  git am patch