[fpc-pascal] When are used units recompiled?

[Micha Nelissen]

On Thu, 6 Apr 2006 11:15:49 +0200 (CEST)
Michael Van Canneyt <michael at freepascal.org> wrote:

> On Wed, 5 Apr 2006, Micha Nelissen wrote:
> 
> > I'm not saying people shouldn't read manuals...just saying that "Can't find
> > unit" can be split up in 3 or so "causes", and a more helpful message given
> > for each of them.
> 
> That may be harder than you think, because the routines looking for a unit
> source do not know WHY they are looking for this. 

*Now* we are getting somewhere, the compiler source structure does not lend
itself well to have a more helpful message. This is a perfectly fine
argument.
 
> So they just report 'sorry, we didn't find what you requested".
> (you=other compiler routines)
> 
> At the moment when the compiler decides it needs to recompile a unit 
> and starts looking for sources, it doesn't know yet whether it will 
> find it or not, so it has no sense outputting a message then.
> You would get far too many messages.

No, of course you don't want it to say something for every unit, that's
what -va/-vu are for.
 
> Yes, you could pass on a 'reason' why a unit is searched, and then 
> output that, but it would make the compiler slower and more complicated.

Are you sure? Passing one flag? Checking whether a file exists is probably
way more expensive than passing a flag.

> So, for this, you need to use -vu. Then you can follow the compiler's 
> logic exactly...
> 
> Which doesn't mean we shouldn't maybe rephrase some messages, but just 
> don't get your hopes up too high :-)

Sure, I can understand some things are difficult to implement, and not high
priority for whatever reason, but please do not "hide" behind manuals.

Therefore, I ask again to reopen bug report 4691. Not that it has to be
fixed now, next week, or ever, for that matter; simply leave it open as a
wishlist item.

As somebody else suggested, I may try myself; but I also have a TODO list
like you :-).

Micha