[m-rev.] for review: update README.macOS.md

[Zoltan Somogyi]

On Wed, 14 May 2025 14:16:22 +1000, Julien Fischer <jfischer at opturion.com> wrote:
> -Versions of macOS prior to 10.9 are not supported.
> +Versions of macOS prior to 10.9 are not supported. Both Intel and Apple Silicon
> +Macs are supported, although the latter has not been extensively tested.

I would change both sentences to use the active voice, with "Mercury supports ...".

> @@ -49,18 +49,18 @@ or
> 
>  depending on their preferred compiler. In either case, every invocation
>  of the selected C compiler on Mercury-generated C files will specify
> -the `-m32` option. The reason for the limitation to 10.14 is that
> +the `-m32` option. The reason for the restriction to version 10.14 is that
>  32-bit executables are not supported at all from macOS 10.15 onwards.

Again, switch to active voice, and say that it is *Apple* that does not support
32-bit executables on those versions.

>  If, after installing Mercury, you encounter errors about missing `.mih` files,
> -and you have fink installed, then try removing the fink components from your
> -`PATH` (these usually start with `/sw`) and reinstalling.
> +and you have fink installed,try removing the fink components from your `PATH`
> +(these usually start with `/sw`) and reinstalling.

How can fink interfere with .mih files? If the answer is not too complex, it would be
worthwhile including it here.

Also, add a space the command and "try".
 
>  Note for users of Xcode 11
>  --------------------------
> 
>  Versions of Xcode 11 prior to 11.4 ship with a broken version of `clang`
> -that *cannot* be used to compile Mercury.  The `configure` script will print
> +that *cannot* be used to compile Mercury. The `configure` script will print
>  a warning if it detects that you are using the broken version.

The diff is otherwise fine.

Zoltan.