On 04.02.2025 14:56, Andrew Cooper wrote:
> On 04/02/2025 1:19 pm, Jan Beulich wrote:
>> On 04.02.2025 14:10, Andrew Cooper wrote:
>>> On 04/02/2025 1:03 pm, Jan Beulich wrote:
>>>> --- a/xen/include/xen/radix-tree.h
>>>> +++ b/xen/include/xen/radix-tree.h
>>>> @@ -72,6 +72,9 @@ struct radix_tree_root {
>>>> *** radix-tree API starts here **
>>>> */
>>>>
>>>> +#define RADIX_TREE_INIT() {}
>>>> +#define RADIX_TREE(name) struct radix_tree_root name = RADIX_TREE_INIT()
>>> We can still use this form in radix_tree_init(), can't we?
>> Only indirectly, and that's imo ugly:
>>
>> void radix_tree_init(struct radix_tree_root *root)
>> {
>> RADIX_TREE(init);
>>
>> *root = init;
>> }
>>
>> RADIX_TREE_INIT() cannot (directly) be used because {} isn't an rvalue.
>
> Even if it's not ideal,
>
> *root = *(struct radix_tree_root)RADIX_TREE_INIT();
>
> works. We use this pattern elsewhere in Xen, so it surely will be fine
> even on ancient compilers.
Hmm, yes, with the * on the rhs dropped this ought to work. I'll switch,
yet at the same time I have to admit that I don't recall having seen this
pattern anywhere in our tree.
Jan
