Re: [PATCH] include: move typeof_strip_qual to compiler.h, use it in QAPI_LIST_LENGTH()

[Richard Henderson <richard.henderson@linaro.org>]

On 6/25/24 04:18, Paolo Bonzini wrote:
> The typeof_strip_qual() is most useful for the atomic fetch-and-modify
> operations in atomic.h, but it can be used elsewhere as well.  For example,
> QAPI_LIST_LENGTH() assumes that the argument is not const, which is not a
> requirement.
> 
> Move the macro to compiler.h and, while at it, move it under #ifndef
> __cplusplus to emphasize that it uses C-only constructs.  A C++ version
> of typeof_strip_qual() using type traits is possible[1], but beyond the
> scope of this patch because the little C++ code that is in QEMU does not
> use QAPI.
> 
> The patch was tested by changing the declaration of strv_from_str_list()
> in qapi/qapi-type-helpers.c to:
> 
>      char **strv_from_str_list(const strList *const list)
> 
> This is valid C code, and it fails to compile without this change.
> 
> [1]https://lore.kernel.org/qemu-devel/20240624205647.112034-1-flwu@google.com/
> 
> Signed-off-by: Paolo Bonzini<pbonzini@redhat.com>
> ---
>   include/qapi/util.h     |  2 +-
>   include/qemu/atomic.h   | 42 -------------------------------------
>   include/qemu/compiler.h | 46 +++++++++++++++++++++++++++++++++++++++++
>   3 files changed, 47 insertions(+), 43 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~