mirror of
https://gitlab.com/buildroot.org/buildroot.git
synced 2026-09-09 07:51:59 -09:00
8138a36018
Some OpenGL/EGL/GLES/VG providers do not provide the corresponding
headers, and rely on using "the headers provided by the distribution".
In our case, we can not rely on such headers, because we are not a
distribution, and we have no way to provide those headers (not even
speaking about relying on the headers provided by hte host distribution,
because they might well not be installed at all).
Also, we can not rely on another package to provide those headers,
because we can only have one provider enabled in any configuration.
The Khronos group provides such headers, and they are the reference
headers, but we can not realy use them:
- most of them are not packaged: they are not versioned and not
provided in a tarball, but as separately downloadable files;
- those headers are anyway incomplete: there are headers not provided
by Khronos, like GL.h
Instead, we rely on mesa3d to provide those headers: mesa3d has all the
headers we need.
Modifying the existing mesa3d package would not be easy; we'd have to
differentiate whther we need only the headers or the full package. The
meas3d Config.in and .mk are already quite non-trivial that adding such
a feature would render them even more illegible.
So, we introduce mea3d-headers as a new package, that is in fact just
mesa3d with a much simplified Config.in and .mk, that other OpenXXX
providers may select if they do not provide the OpenXXX headers.
Note: we're not installing GLES3 headers, because what Buildroot
currently calls libgles is in fact libgles2; we have no way to specify
that we have libgles3. So, we just install headers for GLES and GLES2.
[Thomas:
- Wrap Config.in help text to a reasonable length.
- Don't rely on mesa3d to provide mesa3d-headers: they should be
mutually exclusive. Instead, error out if both packages are
selected.
- Take into account the update of mesa3d to 10.4.5.
- Don't copy each header file individually, use a cp -dpfr call to
copy entires header files directories.]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
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