[yocto] how does one use a prebuilt toolchain from the toolchain/ directory?

[Robert P. J. Day]

On Mon, 2 Jul 2012, Zhang, Jessica wrote:

> On Tue, Jun 26, 2012 at 4:51 AM, Robert P. J. Day <rpjday at crashcourse.ca> wrote:

... snip ...

> > 4) once i install a toolchain, how do i use it?  say i install the arm
> > toolchain, and want to build a beagleboard image.  at what point do i
> > source the arm toolchain environment setup file?  is that all it
> > takes?  will the bitbake build process automatically recognize what
> > i've done and use that toolchain?
>
> [JZ] Please note this toolchain is meant to be used by application
> developers not image builders.  This toolchain is meant for cross
> development that allows you to develop target application on your
> host machines.  Once you source the environment-setup script, it'll
> setup your path correctly that makes it able to find all the cross
> development tools, e.g.
> /opt/poky/1.2/sysroots/i686-pokysdk-linux/usr/bin/i586-poky-linux/i586-poky-linux-gcc
> will be used for compiling your programs.

  ah, i wasn't aware that the prebuilt toolchains were meant primarily
for *app* development, not *image* development.  i already knew how to
use them for app development, that's fairly straightforward.

  which brings me back to my original curiosity -- how can i use the
same toolchain across a number of different *image* builds?  under
what circumstances does that make sense, and how would i do that?

  say i want to configure and build images for a number of
beagleboards, and a beaglebone, and a pandaboard, etc., all of which
require an ARM toolchain.  if these builds can share the same
toolchain, how can i build it once, then not have to build it over and
over for the remaining builds?

rday

-- 

========================================================================
Robert P. J. Day                                 Ottawa, Ontario, CANADA
                        http://crashcourse.ca

Twitter:                                       http://twitter.com/rpjday
LinkedIn:                               http://ca.linkedin.com/in/rpjday
========================================================================