Re: git: ce9e720af2f8 - main - <sys/_pv_entry>: Add a fallback for __LONG_WIDTH__ for older compilers.

From: John Baldwin <jhb_at_FreeBSD.org>
Date: Fri, 07 Oct 2022 20:43:19 UTC
On 10/7/22 1:32 PM, John Baldwin wrote:
> The branch main has been updated by jhb:
> 
> URL: https://cgit.FreeBSD.org/src/commit/?id=ce9e720af2f8fa378e36134bab8a82ebf67c159d
> 
> commit ce9e720af2f8fa378e36134bab8a82ebf67c159d
> Author:     John Baldwin <jhb@FreeBSD.org>
> AuthorDate: 2022-10-07 19:44:31 +0000
> Commit:     John Baldwin <jhb@FreeBSD.org>
> CommitDate: 2022-10-07 19:44:31 +0000
> 
>      <sys/_pv_entry>: Add a fallback for __LONG_WIDTH__ for older compilers.
>      
>      clang only includes a __LONG_WIDTH__ builtin in clang 14 and later.
> ---
>   sys/sys/_pv_entry.h | 5 +++++
>   1 file changed, 5 insertions(+)
> 
> diff --git a/sys/sys/_pv_entry.h b/sys/sys/_pv_entry.h
> index 411643cf49ec..3cd0d9c687f6 100644
> --- a/sys/sys/_pv_entry.h
> +++ b/sys/sys/_pv_entry.h
> @@ -77,6 +77,11 @@ typedef struct pv_entry {
>   #error Unsupported page size
>   #endif
>   
> +/* Support clang < 14 */
> +#ifndef __LONG_WIDTH__
> +#define	__LONG_WIDTH__	(__CHAR_BIT__ * __SIZEOF_LONG__)
> +#endif
> +

This was the smallest change to fix CI breakage.  However, we may want to do
this differently.  We could perhaps add this fallback for __LONG_WIDTH__ to
<sys/cdefs.h>, or we could change sys/_pv_entry.h to use the expanded form
always (or pick a different spelling?)

-- 
John Baldwin