Go to file
Yann E. MORIN 2a82bb8a90 support/check-kernel-headers: fix old custom toolchains without -print-sysroot
Old toolchains, with old gcc that do not support -print-sysroot, break the
kernel-headers version check script: it fails to find the sysroot of the
toolchain, and thus ends up including the host's linux/version.h.

Most of the time, this will break early, since the host's kernel headers
will not match the toolchain settings.

But it can happen that the check is succesful, although the configuration
of the toolchain is wrong:

  - the custom toolchain has kernel headers vX.Y
  - the user selected vX.Z  (Z!=Y)
  - the host has headers vX.Y

In this case, the check passes OK, but the build of some packages later on
will break (which is exactly what those _AT_LEAST_XXX options were added to
avoid).

Fix that by passing the sysroot to the check script, instead of the cross
compiler.

We get the sysroot as thus:

  - for custom toolchains, we use the macro toolchain_find_sysroot. We can
    do that, because we already have a complete sysroot with libc.a at that
    time.

  - for internal toolchain using a custom kernel headers version, we just
    use $(STAGING_DIR). We can't use the macro as for custom toolchains
    above, because at the time we install the kernel headers, we do not yet
    have a complete sysroot with a libc.a.  But we can just use
    $(STAGING_DIR), since we're only interested in the kernel headers.

For all other types of toolchains, we already have the _AT_LEAST_XXX options
properly set, so we need not add a check in this case.

Fixes:
    http://autobuild.buildroot.net/results/f33/f331a6eff0b0b93c73af52db3a6b43e4e598577e/
    http://autobuild.buildroot.net/results/a57/a5797c025bec50c10efdcff74945aab4021d05e4/
    [...]

[Thanks to Thomas for pointing out the toolchain_find_sysroot macro!]

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
2014-04-09 01:38:10 +02:00
arch Disable o32 ABI for MIPS64 architectures 2014-03-28 12:51:46 +01:00
board board/arm/foundation-v8: update defconfig and instructions 2014-03-21 07:27:12 +01:00
boot barebox: fix coding style 2014-03-27 23:27:22 +01:00
configs board/arm/foundation-v8: update defconfig and instructions 2014-03-21 07:27:12 +01:00
docs manual: add notes about depending on a virtual package 2014-04-05 19:21:02 +02:00
fs Don't build host-xz needlessly 2014-04-07 21:38:28 +02:00
linux linux: bump to version 3.14 2014-04-01 14:44:36 +02:00
package support/check-kernel-headers: fix old custom toolchains without -print-sysroot 2014-04-09 01:38:10 +02:00
support support/check-kernel-headers: fix old custom toolchains without -print-sysroot 2014-04-09 01:38:10 +02:00
system system: allow setting the local timezone for uClibc 2014-04-09 00:33:32 +02:00
toolchain support/check-kernel-headers: fix old custom toolchains without -print-sysroot 2014-04-09 01:38:10 +02:00
.defconfig buildroot: get rid of s390 support 2009-01-12 14:36:14 +00:00
.gitignore update gitignore 2013-05-04 12:41:55 +02:00
CHANGES Disable o32 ABI for MIPS64 architectures 2014-03-28 12:51:46 +01:00
Config.in uboot: mark custom network settings as deprecated 2014-03-18 09:04:31 +01:00
Config.in.legacy system: make the zoneinfo list a system option 2014-04-08 23:33:24 +02:00
COPYING clarify license and fix website license link 2009-05-08 09:29:41 +02:00
Makefile Add back rootfs-* dependencies to "source" and "legal-info" targets 2014-03-29 12:08:59 +01:00
Makefile.legacy Makefile.legacy: fix recursive invocation with BUILDROOT_DL_DIR and _CONFIG 2014-02-11 08:14:57 +01:00
README docs: Move README file to root 2014-03-03 21:28:39 +01:00

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