[oe] How to select specific version of dependant component

[Martin Jansa]

On Fri, Jun 25, 2010 at 02:03:17PM +1100, Andrew Tverdohlebov wrote:
> >its an override. if you want to know what overrides are read the manual.
> >and in future don't top post its not readable flow.
> 
> If you look into the OpenEmbedded User Manual yourself smart guy,
> you will probably find that the section "overrides" is a stub.
> There is also nothing usefull regarding purpose of  '_local'

description in bitbake.conf

# Overrides are processed left to right, so the ones that are named later take precedence.
# You generally want them to go from least to most specific.
# 
# This means that an envionment variable named '<foo>_arm' overrides an
# environment variable '<foo>' (when ${TARGET_ARCH} is arm).
# an environment variable '<foo>_ramses' overrides '<foo>' but doesn't override
# '<foo>_arm' when ${MACHINE} is 'ramses'. 
# If you use combination ie '<foo>_arm_ramses', then '<foo>_arm_ramses' will override 
# '<foo>_arm' and then '<foo>' will be overriden with that value from '<foo>_arm'.
# And finally '<foo>_local' overrides anything, but with lowest priority.
#
# This works for  functions as well, they are really just environment variables.
# Default OVERRIDES to make compilation fail fast in case of build system misconfiguration.
OVERRIDES = "local:${MACHINE}:${DISTRO}:${TARGET_OS}:${TARGET_ARCH}:build-${BUILD_OS}:fail-fast:pn-${PN}"
# Alternative OVERRIDES definition without "fail fast", usually only for native building and Scratchbox toolchains.
#OVERRIDES = "local:${MACHINE}:${DISTRO}:${TARGET_OS}:${TARGET_ARCH}:build-${BUILD_OS}:pn-${PN}"

-- 
Jansa 'JaMa' Martin     jabber: Martin.Jansa at gmail.com