Re: [PATCH net-next] tools: lib: bpf: libbpf: fix max() type mistmatch for 32bit

From: Andrii Nakryiko
Date: Tue Jun 25 2019 - 13:46:03 EST


On Tue, Jun 25, 2019 at 7:12 AM Ivan Khoronzhuk
<ivan.khoronzhuk@xxxxxxxxxx> wrote:
>
> It fixes build error for 32bit coused by type mistmatch

typo: coused -> caused, mistmatch -> mismatch

> size_t/unsigned long.
>
> Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@xxxxxxxxxx>
> ---
>
> Based on net-next/master

libbpf changes should be based against bpf-next. Indicate that also
with [PATCH bpf-next] subject prefix.

Also, there is no need to have this long "tools: lib: bpf: libbpf:"
prefix, it's not supposed to be a repeat of file path. Use just
"libbpf: " to indicate it's libbpf-related changes.


>
> tools/lib/bpf/libbpf.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
> index 4259c9f0cfe7..d03016a559e2 100644
> --- a/tools/lib/bpf/libbpf.c
> +++ b/tools/lib/bpf/libbpf.c
> @@ -778,7 +778,7 @@ static struct bpf_map *bpf_object__add_map(struct bpf_object *obj)
> if (obj->nr_maps < obj->maps_cap)
> return &obj->maps[obj->nr_maps++];
>
> - new_cap = max(4ul, obj->maps_cap * 3 / 2);
> + new_cap = max((size_t)4, obj->maps_cap * 3 / 2);

The fix itself works, thanks!

> new_maps = realloc(obj->maps, new_cap * sizeof(*obj->maps));
> if (!new_maps) {
> pr_warning("alloc maps for object failed\n");
> --
> 2.17.1
>