Re: [PATCH] vPCI: resolve MISRA R10.1 boolean arithmetic type violation

[Jan Beulich <jbeulich@xxxxxxxx>]

(extending Cc list)

On 22.05.2026 08:13, Dmytro Prokopchuk1 wrote:
> --- a/xen/drivers/vpci/header.c
> +++ b/xen/drivers/vpci/header.c
> @@ -586,7 +586,7 @@ static void cf_check bar_write(
>          if ( val != (uint32_t)(bar->addr >> (hi ? 32 : 0)) )
>              gprintk(XENLOG_WARNING,
>                      "%pp: ignored BAR %zu write while mapped\n",
> -                    &pdev->sbdf, bar - pdev->vpci->header.bars + hi);
> +                    &pdev->sbdf, bar - pdev->vpci->header.bars + (hi ? 1 : 
> 0));
>          return;
>      }
>  
> @@ -647,7 +647,7 @@ static void cf_check guest_mem_bar_write(const struct 
> pci_dev *pdev,
>          if ( guest_addr != bar->guest_addr )
>              gprintk(XENLOG_WARNING,
>                      "%pp: ignored guest BAR %zu write while mapped\n",
> -                    &pdev->sbdf, bar - pdev->vpci->header.bars + hi);
> +                    &pdev->sbdf, bar - pdev->vpci->header.bars + (hi ? 1 : 
> 0));
>          return;
>      }
>      bar->guest_addr = guest_addr;

Well. If I'm not mistaken we had discussed situations like this (long ago).
Imo the added verbosity gets in the way of readability. If we absolutely
cannot or don't want to deviate such constructs (of which I expect we have
more), then we ought to consider alternatives (like changing the variables'
types in the case here).

As to deviating: rules.rst, according to my reading, says that &, |, ^, or
shifts would be okay to use with a bool operand. What's wrong with also
permitting this for other operators?

Jan