Re: [PATCH 1/1] target/arm: Adding a check for the result of calling the CPU information check function

[Peter Maydell <peter.maydell@linaro.org>]

On Thu, 12 Oct 2023 at 09:57, Sergey Mironov <mironov@fintech.ru> wrote:
>
> 6 out of 7 calls to get_arm_cp_reginfo() are checked

This sounds like it's talking about a Coverity warning, though
it doesn't say so. Is that the motivation here ? If so,
it would be good to say so in the commit message. If not,
the commit message should explain why we're making the change.

That particular Coverity warning is quite prone to false
positives, since it's only a heuristic. Sometimes it's
useful to add an assert(), if it helps both Coverity and
human readers, but not always.

assert()s are also most useful if there's a comment that explains
why we can assume the thing they're assuming, as Alex suggests.

> Signed-off-by: Sergey Mironov <mironov@fintech.ru>
> ---
>  target/arm/helper.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/target/arm/helper.c b/target/arm/helper.c
> index 74fbb6e1d7..cffbbaf571 100644
> --- a/target/arm/helper.c
> +++ b/target/arm/helper.c
> @@ -198,6 +198,7 @@ static void add_cpreg_to_list(gpointer key, gpointer opaque)
>      uint32_t regidx = (uintptr_t)key;
>      const ARMCPRegInfo *ri = get_arm_cp_reginfo(cpu->cp_regs, regidx);
>
> +    assert(ri != NULL);

>      if (!(ri->type & (ARM_CP_NO_RAW | ARM_CP_ALIAS))) {
>          cpu->cpreg_indexes[cpu->cpreg_array_len] = cpreg_to_kvm_id(regidx);
>          /* The value array need not be initialized at this point */
> --
> 2.31.1

thanks
-- PMM