Compiling Qt fro Raspberry pi 2

Hack ERA · wrote on 24 Mar 2015, 10:06

Hello,

Is there any special requirements to compile QT5 for rpi2? I mean some tuning parameters for cpu? I made linux-rasp-pi2-g++ and added the fallowing parameters in qmake.conf:
-marm
-mfpu=neon-vfpv4
-mtune=cortex-a7
-mabi=aapcs-linux
-mcpu=cortex-a7
-mfloat-abi=hard.

Is it correct? or I wasted time for it?

sierdzio · 24 Mar 2015, 10:23

Looks fine. Does it compile?

Hack ERA · wrote on 24 Mar 2015, 10:23

@sierdzio

Yes it compiled and works fine, but if there is some more tuning parameters available for rpi2 please let me know.

_nezticle · 30 Mar 2015, 13:06

A device mkspec was added for Raspberry Pi 2 in 5.5 branch:
http://code.qt.io/cgit/qt/qtbase.git/tree/mkspecs/devices/linux-rasp-pi2-g++/qmake.conf

Hack ERA · wrote on 30 Mar 2015, 11:26

Thank you

AQTStudent · wrote on 30 Mar 2015, 13:06

@_nezticle
Can you explain me what this means and what this has as extra opposed to not having this?

SGaist · 30 Mar 2015, 22:06

@jorricks the device mkspec provides Qt's build system with default/optimized parameters suited to build Qt specifically for that device

AQTStudent · S SGaist 30 Mar 2015, 21:53

@SGaist
Thank you for your reply!
Sorry for asking the following question here but I figured you'd probably know it

paulo@westeros:~/opt/qt5/qtimageformats$ /usr/local/qt5pi/bin/qmake .
It says my qmake can not be found.. Do you have any clue what this step actually should be then?
(following http://qt-project.org/wiki/RaspberryPi_Beginners_guide)

Kind regards,

SGaist · 30 Mar 2015, 22:11

Did you first install the Qt version your just built ?

AQTStudent · 8 May 2015, 19:34

@SGaist Ah.. The instruction should have been /mnt/rasp-pi-rootfs/usr/local/qt5pi/bin/qmake .
sorry for bothering you!

tcbetka · wrote on 8 May 2015, 19:34

@jorricks Indeed... I noticed this too last night, when I was working through the tutorial. I got Qt5 to build, but there were a number of library path problems--so I ended up just scrapping the entire build, and installing Qt4 from the repositories.

It doesn't yet appear that the RPi2 Model B is quite ready for prime-time, at least where Qt5 is concerned. I am sure that people are getting it to work--but it isn't exactly straightforward at this time, and there do seem to be problems left to solve once the build completes.

TB

AQTStudent · wrote on 15 May 2015, 18:44

@tcbetka said:

It doesn't yet appear that the RPi2 Model B is quite ready for prime-time, at least where Qt5 is concerned. I am sure that people are getting it to work--but it isn't exactly straightforward at this time, and there do seem to be problems left to solve once the build completes.

Eay TCBetka,
There is a tutorial now that let's you build it nativly on the raspberry pi 2. Works like a charm!
Caution though, you will not be able to cross-compile I believe.
Kind regards,

mrz28s · wrote on 21 May 2015, 21:02

@_nezticle Stupid noob question.... (So sorry.. I'm learning!)

I have a Raspberry Pi2, I would like to get 5.5.0-beta working on it. (or any other slightly earlier version for that matter)
You mentioned they have "a device mkspec was added for Raspberry Pi 2 in 5.5 branch:"

So I downloaded the qt-everywhere-opensource-src-5.5.0-beta and I would like to get it installed on my Pi 2.
What command do I use to get it to successfully install on my Raspberry Pi 2?

Do I use ./configure -prefix $PWD/qtbase -opensource -nomake tests like the README says or do I add something else to get it to install for just the Pi 2?

Ultimately I'd like to install Qt Creator 3.4.0 (or maybe an earlier version?) so I can run .pro files that cryptocurreny wallets have available. [eg. https://github.com/sherlockcoin/navajocoin (the NavajoCoin-qt.pro file)]

Here's what I see:
Build instructions

Debian

First, make sure that the required packages for Qt5 development of your distribution are installed, for Debian and Ubuntu these are:

apt-get install qt5-default qt5-qmake qtbase5-dev-tools qttools5-dev-tools
build-essential libboost-dev libboost-system-dev
libboost-filesystem-dev libboost-program-options-dev libboost-thread-dev
libssl-dev libdb++-dev
then execute the following:

qmake
make
Alternatively, install Qt Creator and open the navajocoin-qt.pro file.

An executable named navajocoin-qt will be built.

I've tried the 1st part, and it won't work (probably because this is a Pi 2 I'm assuming)
So, I need help with the 2nd part.

Many Many Thanks to anybody that can help me!