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

[Bob Friesenhahn]

On Mon, 8 Mar 2021, Paul Eggert wrote:

> Except maybe for Solaris 10, shells that don't grok $(...) are museum pieces 
> now. And anybody on Solaris 10 (which occasionally includes me, as my 
> department still uses Solaris 10 on some machines) can easily run a better 
> shell like /bin/ksh. It's a bit of a maintenance hassle for Ben to deal with

The script itself does start with requesting /bin/sh.  The 
config.guess script is also used in contexts outside of Autotools, 
although such usage can likely specify the shell to use when executing 
the script.

> At some point, failing to support $(...) is in the same ballpark as failing 
> to support "#". I can see Ben's point of view that we've reached that point 
> even if I would have waited another three years, so if Ben would rather use 
> $(...) I'd rather not overrule him downstream.

It seems that config.guess and Autotools packages are picking winners 
and losers.  It is not clear where the bar has been set.  When such 
decisions are made, it is useful if messaging about it is very clear.

If any component of a build infrastructure is not portable to an older 
system, then all of the components (including each dependent 
application's own configure.ac script) might as well be updated to use 
the less-portable yet more convenient modern syntax and this implies 
the ability to safely use other modern syntax as well.

Bob
--
Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/
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