Re: sysroot support in libtool

[Ralf Wildenhues]

* Richard Purdie wrote on Mon, Apr 14, 2008 at 12:42:04AM CEST:
> On Sun, 2008-04-13 at 22:26 +0200, Ralf Wildenhues wrote:
> 
> > > tag.patch - The tag errors were breaking things for no good reason so we
> > > turned the error into a warning
> > 
> > Well, don't come crying for bad performance to us if you do things like
> > this.  Letting libtool infer the tag is rather expensive, at least
> > relatively, for 2.2.2 on modern systems where there are few other forks
> > needed.
> 
> Going totally from memory, I think this exists since we have CC set to
> things like:
> 
> CC="gcc -march=armv5te -mtune=xscale"
> 
> and then this might change to
> 
> CC="gcc -march=armv5te -mtune=arm926ejs"
> 
> which is 100% binary compatible, just optimised differently. libtool
> upon seeing CC change gets "upset". Sadly I can't remember how libtool
> notices this change, it much be through some kind of state information
> libtool saves into our staging area.

It will not get upset if you pass --tag=CC (for each mode), and use your
changed $CC for compile mode.

However, it will happily ignore your changed $CC for link mode when
creating shared libraries.  That may or may not be a problem for you,
but it will anyway not be solved by your patch.

Cheers,
Ralf