Yann E. MORIN 5ab8018539 docs/manual: use space-separated list for BR2_EXTERNAL
Specifying a list of br2-external trees is poorly documented, and the
only example uses a colon to separate the br2-external paths.

Adding the support for colon-separated list is the biggest mistake that
was made when introducing support for multiple br2-external [0]. Indeed,
both space and colon can be used to separate entries in the list, and it
is also possible to mix the two. However, internally, the list is stored
as a space-separated list, and all the code will split on spaces.

Besides, all other lists in Buildroot are a space-separated:
    BR2_ROOTFS_DEVICE_TABLE
    BR2_ROOTFS_STATIC_DEVICE_TABLE
    BR2_TARGET_TZ_ZONELIST
    BR2_ROOTFS_USERS_TABLES
    BR2_ROOTFS_OVERLAY
    BR2_ROOTFS_PRE_BUILD_SCRIPT
    BR2_ROOTFS_POST_BUILD_SCRIPT
    BR2_ROOTFS_POST_FAKEROOT_SCRIPT
    BR2_ROOTFS_POST_IMAGE_SCRIPT
    ...

So, using colons is odd.

The fact that BR2_EXTERNAL is passed on the command line rather than
being a Kconfig item is not a reason enough to justify that it be
colon-separated.

Change the documentation to only mention using a space-separated list.

Of course, for backward compatibility, we keep the code as-is to accept
a colon-separated list, but we just do not advertise it.

Note that keeping the split on colons means that colons are not accepted
in pathnames of br2-external trees; in practice, this is not a new
restriction, or one that could lift as usign colons in Makefiles are
problematic anyway.

[0] in 20cd497387 core: add support for multiple br2-external trees

Reported-by: Fiona Klute (WIWA) <fiona.klute@gmx.de>
Reported-by: Brandon Maier <Brandon.Maier@collins.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
Cc: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Romain Naour <romain.naour@smile.fr>
(cherry picked from commit f9cdca48a5)
Signed-off-by: Thomas Perale <thomas.perale@mind.be>
2026-03-20 16:52:11 +01:00
2025-01-15 21:30:31 +01:00
2026-03-17 20:42:57 +01:00
2026-03-17 20:48:33 +01:00
2026-01-15 09:36:08 +01:00

Buildroot is a simple, efficient and easy-to-use tool to generate embedded
Linux systems through cross-compilation.

The documentation can be found in docs/manual. You can generate a text
document with 'make manual-text' and read output/docs/manual/manual.text.
Online documentation can be found at https://buildroot.org/docs.html

To build and use the buildroot stuff, do the following:

1) run 'make menuconfig'
2) select the target architecture and the packages you wish to compile
3) run 'make'
4) wait while it compiles
5) find the kernel, bootloader, root filesystem, etc. in output/images

You do not need to be root to build or run buildroot.  Have fun!

Buildroot comes with a basic configuration for a number of boards. Run
'make list-defconfigs' to view the list of provided configurations.

Please feed suggestions, bug reports, insults, and bribes back to the
buildroot mailing list: buildroot@buildroot.org
You can also find us on #buildroot on OFTC IRC.

If you would like to contribute patches, please read
https://buildroot.org/manual.html#submitting-patches
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