[PATCH 1/5] maple_tree: Move the check forward to avoid static check warning.

[Liam R. Howlett]

* Peng Zhang <zhangpeng.00 at bytedance.com> [231109 07:43]:
> Put the check for gap before its reference to avoid Smatch static check
> warnings. This is not a bug, it's just a validation program.
> 
> Reported-by: Dan Carpenter <dan.carpenter at linaro.org>
> Closes: http://lists.infradead.org/pipermail/maple-tree/2023-November/003046.html
> Signed-off-by: Peng Zhang <zhangpeng.00 at bytedance.com>
> ---
>  lib/maple_tree.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/lib/maple_tree.c b/lib/maple_tree.c
> index aaba453b0d30..1dfbcb74787a 100644
> --- a/lib/maple_tree.c
> +++ b/lib/maple_tree.c
> @@ -7249,6 +7249,11 @@ static void mas_validate_gaps(struct ma_state *mas)
>  
>  counted:
>  	if (mt == maple_arange_64) {
> +		if (!gaps) {
> +			MT_BUG_ON(mas->tree, 1);
> +			return;

Since MT_BUG_ON() will BUG_ON(), is there a reason to return?

The only reason I've used braces to BUG_ON() is to include extra error
text, but you haven't provided any here.  I think you could do this (or
MT_BUG_ON() variant, if you prefer):

MAS_BUG_ON(mas, gaps == NULL);

> +		}
> +
>  		offset = ma_meta_gap(node, mt);
>  		if (offset > i) {
>  			pr_err("gap offset %p[%u] is invalid\n", node, offset);
> @@ -7261,7 +7266,6 @@ static void mas_validate_gaps(struct ma_state *mas)
>  			MT_BUG_ON(mas->tree, 1);
>  		}
>  
> -		MT_BUG_ON(mas->tree, !gaps);
>  		for (i++ ; i < mt_slot_count(mte); i++) {
>  			if (gaps[i] != 0) {
>  				pr_err("gap %p[%u] beyond node limit != 0\n",
> -- 
> 2.20.1
>