How to install gcc

Boken Lin

@Johan-Simons If you can tell me the version of Linux you are using I can create the SDK for you.

Boken Lin

@Justin-Sowers The Omega (or most OpenWRT devices for that matter) has very limited computational resources, so people don't generally compile anything directly on them, which is probably why you are unable to find packages that allow you to install build tools. However, things like make and autoconf are just binaries that can you compiled from source. So if you want to compile it for the Omega, it's simply a matter of creating a Makefile in your cross-compile environment and build an opkg package out of them.

Kit Bishop

@Boken-Lin I read the post from @Justin-Sowers as meaning he wanted to be able to do the build actually on the Omega itself having made more space available via the overlay method. Though I'm sure you could give a more definitive response to this, it would seem to me that this would not be possible, not because of (disk) storage space but because of RAM limitations.
Any comments?

Boken Lin

@Kit-Bishop RAM is definitely a limitation. However, I think if he sets up a swap partition on the USB drive it might just work.

Kit Bishop

@Boken-Lin Setting up a swap partition should help there. Any suggestions as to how to go about this on the Omega? If not, I will have a look myself to see if I can figure something out.

That would just leave the need to have access to Omega packages etc. for gcc, make etc. and any other needed utils.

Boken Lin

@Kit-Bishop Yeah, it should be pretty straight forward. Remember /etc/config/fstab from setting up rootfs? You just need to add a few more lines to enable swap:

For swap partition

config 'swap'
        option  device  'sda1'
        option  uuid    'xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx'

Swap file

config 'swap'
        option  device  '/mnt/shared/swap'

Swap device by label (mkswap -L swap /dev/sdb2)

config 'swap'
        option  label 'swap'

Save the file and reboot.

Kit Bishop

@Boken-Lin Thanks - I'll give it a try.
Since I already use my USB device for /overlay, presumably I will need to re-partition my USB drive with two partitions:

An ext4 partition for /overlay
A swap partition for swap

Any suggestions as to what would be a suitable size for the swap partition?

Also, once all details are ironed out, perhaps the details should be made the subject of a Wiki tutorial (with reference too to the usage of the USB drive for overlay and swap)

Boken Lin

@Kit-Bishop You can try a swap of 512MB, it should be enough for compilation purposes.

And yup, I will write up a separate tutorial for that.

Kit Bishop

@Boken-Lin I have had a try at setting up swap on a USB drive partition and believe it is actually working. My Omega still works fine after the steps I describe below and as shown below I believe I have the expected swap space. Note in the steps I describe below I wanted to maintain a partition on the USB drive for overlay.

Steps I have performed and some associated information are:

Partitioned my USB drive with 2 partitions as follows:
- Partition 1: 100MByte partitioned as linuxswap
- Partition 2: Rest of drive as ext4 partition for overlay
Performed the steps necessary to use partition 2 for /overlay directory
Resultant /etc/config/fstab is:
config 'global'
option anon_swap '0'
option anon_mount '0'
option auto_swap '1'
option auto_mount '1'
option delay_root '5'
option check_fs '0'

config 'swap'
option device 'sda1'
option uuid 'b1b4771d-fc9c-4cc9-811d-04f4f8a8925d'
option enabled '1'

config 'mount'
option target '/overlay'
option uuid 'b2580ec6-6d9f-4514-930a-df481be20b99'
option enabled '1'
4. Output from the free command before setting up the swap was:
total used free shared buffers
Mem: 61180 27184 33996 92 3484
-/+ buffers: 23700 37480
Swap: 0 0 0
5. Output from the free command after setting up the swap is:
total used free shared buffers
Mem: 61180 28092 33088 92 3644
-/+ buffers: 24448 36732
Swap: 1028124 0 1028124
This seems to indicate that swap is operative

Johan Simons

@Boken-Lin
I am using CentOS 6.5
Getting a specific toolchain would be great
thx

Johan Simons

@Boken-Lin
Hi there, is there any progress on the issue of a toolchain for 32bit CentOS 6.5 ???
thx

Boken Lin

Hi @Johan-Simons, please download the SDK Here: https://s3-us-west-2.amazonaws.com/onion-downloads/openwrt/OpenWrt-SDK-ar71xx-generic_gcc-4.8-linaro_uClibc-0.9.33.2.Linux-i686.tar.bz2.
The Toolchain is here: https://s3-us-west-2.amazonaws.com/onion-downloads/openwrt/OpenWrt-Toolchain-ar71xx-generic_gcc-4.8-linaro_uClibc-0.9.33.2.Linux-i686.tar.bz2

Cheers!

Johan Simons

@Boken-Lin said:

Hi @Johan-Simons, please download the SDK Here: https://s3-us-west-2.amazonaws.com/onion-downloads/openwrt/OpenWrt-SDK-ar71xx-generic_gcc-4.8-linaro_uClibc-0.9.33.2.Linux-i686.tar.bz2.
The Toolchain is here: https://s3-us-west-2.amazonaws.com/onion-downloads/openwrt/OpenWrt-Toolchain-ar71xx-generic_gcc-4.8-linaro_uClibc-0.9.33.2.Linux-i686.tar.bz2

Cheers!

It is working, thx for the solution

Boken Lin

@Johan-Simons Awesome!

Justin Sowers

@Kit-Bishop @Boken-Lin Could you write-up a quick guide to setting-up a swap partition? I think the bones are in this thread, but not the full guide. I have compiled make, m4, and autoconf from source on the Omega, and have successfully installed them, as well as a few other pieces of software. However, building and running bigger tools like SWIG, likely needs swap. I intend to use SWIG to generate a Ruby extension for the C++ new-gpio lib. BtW, other than running a little slow, the Omega is a fine build machine.

Kit Bishop

@Justin-Sowers I will write a quick guide for this and post it here in a .pdf file - keep watching.
@Boken-Lin When I have done the guide, would it be a suitable candidate for a Wiki Tutorial?

Kit Bishop

@Justin-Sowers @Boken-Lin I have created a new post (https://community.onion.io/topic/533/using-linux-swap-space-on-the-omega) that contains the guide.
Hope it is useful.

Ahmed Mkadem

@Kit-Bishop then how can you compile a C program ? can you explain it to me please ?

Kit Bishop

@Ahmed-Mkadem I compile C/C++ using cross compilation on a Linux system (I use Kubuntu).
Some details can be found at https://community.onion.io/topic/9/how-to-install-gcc/22

You may also be interested in the set of C++ libraries and programs I have produced for perfroming GPIO, I2C and Arduino access on the Omega. The full set of these can be found at https://github.com/KitBishop/Omega-GPIO-I2C-Arduino The various documentation .pdf files therein give more details.

You might in particular look at the template program that is included in the above referenced package - see https://github.com/KitBishop/Omega-GPIO-I2C-Arduino/tree/master/iotemplate and its documentation at https://github.com/KitBishop/Omega-GPIO-I2C-Arduino/blob/master/iotemplate/iotemplate.pdf

Hope that helps

Ahmed Mkadem

@Kit-Bishop Thank you !! this is helpful