Re: [PATCH] config.sub: Accept LLVM-style $cpu-$vendor-windows-cygnus

[Zack Weinberg]

On Mon, Sep 25, 2023, at 10:08 PM, Jacob Bachmeyer wrote:
> Zack Weinberg wrote:
>> On Thu, Sep 21, 2023, at 9:49 PM, Jacob Bachmeyer wrote:
>>   
>>> I further argue that alternate output modes should only be supported
>>> at config.sub; config.guess should always produce the current hyphen-
>>> delimited tuple format.
>>
>> That would preclude autoconf using the new format.  We don't want to
>> have to run both config.sub and config.guess, only one or the other
>> depending on whether there were --build/--host/--target options on the
>> command line.
>
> Passing each tuple through config.sub to canonicalize 
> and parse it should not be a serious problem.

Yeah, I partially take this back.  I was concerned with the
maintenance burden, not the performance; in particular we do
not want to have to have

eval `config.sub --output=sh \`config.guess\``

because of the nested backticks.  But if we could instead do

eval `config.guess | config.sub --stdin --output=sh`

then it would be fine.

zw