Re: autoconf is the wrong tool to use

[Mike Stump <mrs at apple dot com>]

On Wednesday, April 23, 2003, at 02:58 PM, Kean Johnston wrote:
> I am convinced that autoconf is the wrong tool to be using
> in GCC. Its fine for detecting host features we need to
> do a bootstrap but it is (IMHO) totally inappropriate for
> detecting any target parameters whatsoever.

No.  It is appropriate, you just have to understand the design.  :-)

Think of autoconf as a feature extraction mechanism.  Given M and Q and 
T, it yields A.  M is the running machine (with environment).  Q are 
all the questions we are interested in having answers to, and T is the 
target triplet.  Normally in native build (M is of type T), the answers 
(A) are determined by running code snippets.  However, that is not 
required by the design.  It is perfectly permissible for autoconf to 
consult a web page populated with static answers that are generated by 
hand, by an oracle, or by a previous run of snippets on some other 
machine.  Given Q and T (ignoring M), it can still yield A.

If there are multiple sets of answers per T, then, imagine if T is 
augmented with out of band information that can map to exactly one set 
of answers for A.

You can see how config.cache fits into such a scheme, just a cache of 
answers to previous questions.

So, maybe you want to enhance autoconf to do something more?