mirror of
https://gitlab.com/buildroot.org/buildroot.git
synced 2026-09-09 07:51:59 -09:00
0aa9019c2d
Since we introduced the _AT_LEAST_XXX for the kernel headers, people using pre-built custom toolchain now have to specify the version of the kernel headers their custom toolchain uses. So, when we detect that there is a mismatch between the selection in the menuconfig, and the actual version of the headers, we currently only bail out with a terse message "Incorrect selection of kernel headers". This could be confusing some, and getting the version of the headers used by the toolchain is not trivial (well, it's very easy, but not trivial.) This patch changes the way we report the error by moving the message into the test-code, and by printing the expected and actual versions of the kernel headers. BUT! To get this pretty error message, we need to run the test-program, so we can not use the cross-toolchain, we have to use the native one. BUT! The native one has its own linux/version.h header, so we can not simply include it. So, we ask the cross-compiler where its default sysroot is, and use that to then force-feed the cross linux/version.h to the native toolchain. [Thomas: augment commit log with a message provided by Yann, fix coding style to not have spaces after opening parenthesis and before closing parenthesis, reformatted the message "Incorrect selection..." to make it fit on one line.] Reported-by: Maxime Hadjinlian <maxime.hadjinlian@gmail.com> Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Cc: Maxime Hadjinlian <maxime.hadjinlian@gmail.com> Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
To build and use the buildroot stuff, do the following:
1) run 'make menuconfig'
2) select the packages you wish to compile
3) run 'make'
4) wait while it compiles
5) Use your shiny new root filesystem. Depending on which sort of
root filesystem you selected, you may want to loop mount it,
chroot into it, nfs mount it on your target device, burn it
to flash, or whatever is appropriate for your target system.
You do not need to be root to build or run buildroot. Have fun!
Offline build:
==============
In order to do an offline-build (not connected to the net), fetch all
selected source by issuing a
$ make source
before you disconnect.
If your build-host is never connected, then you have to copy buildroot
and your toplevel .config to a machine that has an internet-connection
and issue "make source" there, then copy the content of your dl/ dir to
the build-host.
Building out-of-tree:
=====================
Buildroot supports building out of tree with a syntax similar
to the Linux kernel. To use it, add O=<directory> to the
make command line, E.G.:
$ make O=/tmp/build
And all the output files (including .config) will be located under /tmp/build.
More finegrained configuration:
===============================
You can specify a config-file for uClibc:
$ make UCLIBC_CONFIG_FILE=/my/uClibc.config
And you can specify a config-file for busybox:
$ make BUSYBOX_CONFIG_FILE=/my/busybox.config
To use a non-standard host-compiler (if you do not have 'gcc'),
make sure that the compiler is in your PATH and that the library paths are
setup properly, if your compiler is built dynamically:
$ make HOSTCC=gcc-4.3.orig HOSTCXX=gcc-4.3-mine
Depending on your configuration, there are some targets you can use to
use menuconfig of certain packages. This includes:
$ make HOSTCC=gcc-4.3 linux-menuconfig
$ make HOSTCC=gcc-4.3 uclibc-menuconfig
$ make HOSTCC=gcc-4.3 busybox-menuconfig
Please feed suggestions, bug reports, insults, and bribes back to the
buildroot mailing list: buildroot@buildroot.org