[Scons-users] Custom environment tools evaluated before Configure contexts?

[Mats Wichmann]

On 11/6/23 09:57, Gary Granger wrote:
> We have custom tools that call Configure themselves, which I've assumed 
> is a reasonable thing to do.  (Please let me know if not. :) 

It works, as long as you keep some things in mind: it's optional what to 
do with the caching of configure checks. If you run with --config=force, 
any cached checks are ignored, and as a side effect, the configure 
context works off a *copy* of the passed env; otherwise it can modify it 
in place.  This is why we often see stanzas like:

conf = env.Configure()
env = conf.Finish()

so that we always end up using the modified environment, no matter how 
that instance of SCons was launched.  Of course if your checks don't 
modify the environment in the configure context (conf.env), it makes no 
difference.