[PATCH 2/3] bitset: fix build for GCC without experimental API

[Morten Brørup]

> From: David Marchand [mailto:david.marchand at redhat.com]
> Sent: Tuesday, 15 October 2024 14.11
> 
> For a reason similar to the change on bitops header, hide bitset
> implementation relying on experimental API.
> 
> Fixes: 99a1197647d8 ("eal: add bitset type")
> 
> Signed-off-by: David Marchand <david.marchand at redhat.com>
> ---
>  lib/eal/include/rte_bitset.h | 123 +++++++++++++++++++++++++++++++++++
>  1 file changed, 123 insertions(+)
> 
> diff --git a/lib/eal/include/rte_bitset.h
> b/lib/eal/include/rte_bitset.h
> index 74c643a72a..8ae8425fc2 100644
> --- a/lib/eal/include/rte_bitset.h
> +++ b/lib/eal/include/rte_bitset.h
> @@ -255,7 +255,13 @@ __rte_experimental
>  static inline bool
>  rte_bitset_test(const uint64_t *bitset, size_t bit_num)
>  {
> +#ifdef ALLOW_EXPERIMENTAL_API
>  	return __RTE_BITSET_DELEGATE(rte_bit_test, bitset, bit_num);
> +#else
> +	RTE_SET_USED(bitset);
> +	RTE_SET_USED(bit_num);
> +	return false;
> +#endif
>  }

This looks wrong! The API is exposed, but does nothing.

It is possible to build without ALLOW_EXPERIMENTAL_API; the compiler will emit warnings when using experimental APIs.

If those compiler warnings are not handled as errors, the compiled application will be full of bugs.