问题
Building via Yocto Project,Which variable will be preferred or picked by bitbake for MACHINE ,environment variable or as set in local.conf
回答1:
The answer as usual with bitbake is "it depends" but usually in the case of MACHINE, the environment variable wins.
The preference depends on how the configuration file sets the variable. Typically MACHINE is set with soft assignment (e.g. MACHINE ?= "intel-corei7-64") and soft assignment will not override a environment variable. A normal assignment (MACHINE = "intel-corei7-64") would not respect the environment variable.
回答2:
as set in local.conf
From http://www.yoctoproject.org/docs/latest/mega-manual/mega-manual.html#var-MACHINE
MACHINE Specifies the target device for which the image is built. You define MACHINE in the local.conf file found in the Build Directory.
来源：https://stackoverflow.com/questions/45684816/yocto-bitbake-configuration-for-machine-variable-via-shell-environment-variable