Re: [dpdk-dev] [PATCH v2] lib/bpf: fix clang build warnings for aarch64

[Jerin Jacob <jerinjacobk@gmail.com>]

On Fri, Nov 15, 2019 at 12:18 PM Ruifeng Wang <ruifeng.wang@arm.com> wrote:
>
> Clang has different prototype for __builtin___clear_cache(). It requires
> 'char *' parameters while gcc requires 'void *'.
>
> Clang version 8.0 was used.
> Warning messages during build:
> ../lib/librte_bpf/bpf_jit_arm64.c:1438:26: warning: incompatible pointer
> types passing 'uint32_t *' (aka 'unsigned int *') to parameter of type
> 'char *' [-Wincompatible-pointer-types]
>         __builtin___clear_cache(ctx.ins, ctx.ins + ctx.idx);
>                                 ^~~~~~~
> ../lib/librte_bpf/bpf_jit_arm64.c:1438:35: warning: incompatible pointer
> types passing 'uint32_t *' (aka 'unsigned int *') to parameter of type
> 'char *' [-Wincompatible-pointer-types]
>         __builtin___clear_cache(ctx.ins, ctx.ins + ctx.idx);
>                                          ^~~~~~~~~~~~~~~~~
>
> Fixes: f3e516772464 ("bpf/arm: add prologue and epilogue")
> Cc: jerinj@marvell.com
>
> Signed-off-by: Ruifeng Wang <ruifeng.wang@arm.com>
> Reviewed-by: Phil Yang <phil.yang@arm.com>
> Reviewed-by: Gavin Hu <gavin.hu@arm.com>

Acked-by: Jerin Jacob <jerinj@marvell.com>



> ---
> v2:
> Update commit message for failure reason. (Jerin)
>
>  lib/librte_bpf/bpf_jit_arm64.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/lib/librte_bpf/bpf_jit_arm64.c b/lib/librte_bpf/bpf_jit_arm64.c
> index 8882fee67..a5a5d46f0 100644
> --- a/lib/librte_bpf/bpf_jit_arm64.c
> +++ b/lib/librte_bpf/bpf_jit_arm64.c
> @@ -1435,7 +1435,7 @@ bpf_jit_arm64(struct rte_bpf *bpf)
>         }
>
>         /* Flush the icache */
> -       __builtin___clear_cache(ctx.ins, ctx.ins + ctx.idx);
> +       __builtin___clear_cache((char *)ctx.ins, (char *)(ctx.ins + ctx.idx));
>
>         bpf->jit.func = (void *)ctx.ins;
>         bpf->jit.sz = size;
> --
> 2.17.1
>