Re: config.sub/config.guess using nonportable $(...) substitutions

[David A. Wheeler]

> On Mar 9, 2021, at 5:08 PM, Zack Weinberg <zackw@panix.com> wrote:
> N.B. I changed Autoconf's "find us a better shell" logic in 2.70 to
> include checking for $(...) _specifically because of_ the change being
> debated here.  Configure scripts themselves still use `...`
> nigh-exclusively.

This seems like the right approach: First find a useful shell with $(...), then 
use that shell.
This localized the pain to the “find a shell” bootstrap.
I suspect many program-specific scripts use $(...),
so this will actually *increase* the portability of the final result.

--- David A. Wheeler