[m-rev.] asm_fast.gc on MacOS

[Julien Fischer]

On Wed, 25 Sep 2019, Zoltan Somogyi wrote:

> I just added map_foldl4 to map.m and tree234.m. In the course of
> adding a mention to NEWS, I came across this:
>
> * The asm_fast* and reg* grades now work on 64-bit Intel OS X systems when
>  using GCC as the C compiler.
>  See README.MacOS for further details.
>
> This was true when that paragraph was added in 2014, but I believe
> it hasn't been true for a while now, due to newer gcc versions.
>
> Could someone who knows the full story please update both this
> paragraph and README.MacOS?

The above is fine; I've just bootchecked the compiler in asm_fast.gc
with GCC 9.1 on macOS without encountering any issues.

Julien.