buildroot does not regard config changes

Question

Im playing around with buildroot together with linaro 2016.11 for arm. Im actually building the latest Linux Kernel for the i.MX6 Processors. So far so good.

I have setup the buildroot config with

$ make makeconfig

I have configured an external toolchain (the linaro one). I also configured the uboot to be built. In the uboot section, i had to choose the appropriate board name for the defconfig.

Now the problem:

I have done a full make which was successfull without any errors. After that, i have changed the uboot board name to something which does not exist in the source. Just to make sure everything is working correct.

i have restartet the build process with

$ make uboot-rebuild

to my confusion, the build was sucessfull. After a deeper look to the shell commands, i saw, that the new config was just ignored. I have tried everything without success. It only rebuilds correctly after i do a

$make clean
$make

but this will build the whole thing again and it takes a lot of time.

I hope someone could help me with that and give me some hint.

Thanks.

Answer 1

make <pkg>-rebuild rebuilds the package without applying a new configuration, so what happens is correct.

After changing the U-Boot configuration you have to run make uboot-reconfigure. This command first applies the configuration, then it does the same actions as uboot-rebuild.

See also the Buildroot manual, section Understanding how to rebuild packages.