Failed Cross-Compile: Bad Architecture

dayres

I've run into an issue cross-compiling for the Pi3 and using linux-rpi3-g++ as the device.

./configure -release -opengl es2 -device linux-rpi3-g++ \
-device-option CROSS_COMPILE=~/raspi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian/bin/arm-linux-gnueabihf- \
-sysroot ~/raspi/sysroot -opensource -confirm-license -make libs \
-prefix /usr/local/qt5pi -extprefix ~/raspi/qt5pi -hostprefix ~/raspi/qt5 -v

It appears as though it's specifying armv8-a+crc as the architecture, but it's not valid.

checking for OpenGL ES 2.0... 
/home/dayres/raspi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian/bin/arm-linux-gnueabihf-g++ -c -march=armv8-a+crc -mtune=cortex-a53 -mfpu=crypto-neon-fp-armv8 -pipe -Os -mthumb -std=c++1z -mfloat-abi=hard --sysroot=/home/dayres/raspi/sysroot -O2 -Wall -W -fPIC  -I. -I=/opt/vc/include -I=/opt/vc/include/interface/vcos/pthreads -I=/opt/vc/include/interface/vmcs_host/linux -I../../../mkspecs/devices/linux-rpi3-g++ -o opengles2.o opengles2.cpp
arm-linux-gnueabihf-g++: error: unrecognized argument in option ‘-march=armv8-a+crc’
arm-linux-gnueabihf-g++: note: valid arguments to ‘-march=’ are: armv2 armv2a armv3 armv3m armv4 armv4t armv5 armv5e armv5t armv5te armv6 armv6-m armv6j armv6k armv6s-m armv6t2 armv6z armv6zk armv7 armv7-a armv7-m armv7-r armv7e-m armv8-a iwmmxt iwmmxt2 native
arm-linux-gnueabihf-g++: error: unrecognized command line option ‘-std=c++1z’
Makefile:192: recipe for target 'opengles2.o' failed
make: *** [opengles2.o] Error 1

I believe it is using the arm-linux-gnueabihf-g++ from the pi tools so I'm going to investigate further on that side.

Has anyone seen this and know the solution?

Regards,
Dave

SGaist

Hi and welcome to devnet,

You should search where this +crc is coming from. There's only the armv8-a that is available.

dayres

Thank you! I'm excited to get started with QT on the Pi.

I did investigate and found it in the qtbase/mkspecs/devices/linux-rpi3-g++/qmake.conf file.

I removed the +crc and started getting an error stating that it was not able to determine the destination platform. Also, I'm still receiving the arm-linux-gnueabihf-g++: error: unrecognized command line option ‘-std=c++1z’ error.

Regards,
Dave

SGaist

Which version of the cross-compiler are you using ?

dayres

It looks like gcc version 4.8.3 20140106 (prerelease) (crosstool-NG linaro-1.13.1-4.8-2014.01 - Linaro GCC 2013.11)

I just git cloned raspberrypi/tools as per https://wiki.qt.io/RaspberryPi2EGLFS and changed the -device parameter to linux-rpi3-g++ in the configure step.

Did I make a beginner mistake in doing it this way? First time I've done cross-compiling instead of compiling right on a device.

SGaist

You should check and switch to the 4.9 version. Or replace the -std=c++1z option. It asks the compiler to use the latest standard available. IIRC for 4.8 it was c++1y

dayres

Just as an update....

I switched to the 4.9 and the error messages I was receiving went away even with leaving it at armv8-a+crc .

Now it's tossing lots of garbage characters and the below messages. I'm investigating currently.

Running configuration tests (phase 1)...
/home/dayres/raspi/tools/arm-bcm2708/arm-rpi-4.9.3-linux-gnueabihf/bin/arm-linux-gnueabihf-g++: 1: /home/dayres/raspi/tools/arm-bcm2708/arm-rpi-4.9.3-linux-gnueabihf/bin/arm-linux-gnueabihf-g++:ELF: not found
/home/dayres/raspi/tools/arm-bcm2708/arm-rpi-4.9.3-linux-gnueabihf/bin/arm-linux-gnueabihf-g++: 2: /home/dayres/raspi/tools/arm-bcm2708/arm-rpi-4.9.3-linux-gnueabihf/bin/arm-linux-gnueabihf-g++: cannot open 
                                                                                               : No such file
/home/dayres/raspi/tools/arm-bcm2708/arm-rpi-4.9.3-linux-gnueabihf/bin/arm-linux-gnueabihf-g++: 2: /home/dayres/raspi/tools/arm-bcm2708/arm-rpi-4.9.3-linux-gnueabihf/bin/arm-linux-gnueabihf-g++: @@@@@@00pp@p@@@4�
                                                                                                                4�
 : not found
/home/dayres/raspi/tools/arm-bcm2708/arm-rpi-4.9.3-linux-gnueabihf/bin/arm-linux-gnueabihf-g++: 3: /home/dayres/raspi/tools/arm-bcm2708/arm-rpi-4.9.3-linux-gnueabihf/bin/arm-linux-gnueabihf-g++: Syntax error: word unexpected (expecting ")")
Precompiled-headers support disabled.

<---snip--->
Configures lots of things correctly
<---snip--->

Makefile:193: recipe for target 'arch.o' failed
make: *** [arch.o] Error 2
Unable to determine architecture!

Could not determine the target architecture!
Turn on verbose messaging (-v) to see the final report.
Determining architecture... ()
g++ -c -pipe -g -Wall -W -fPIC  -I. -I../../mkspecs/linux-g++ -o arch.o arch.cpp
g++  -o arch arch.o    
    Found architecture in binary
CFG_HOST_ARCH="i386"
CFG_HOST_CPUFEATURES=""
System architecture: 'unknown'
Host architecture: 'i386'
checking for C++11...

Anyway, just wanted to provide an update on where I was... I'll see how I can make out tonight.

SGaist

Did you do a full rebuild after you changed the compiler ?

kosteltsev

@dayres said:

std=c++1z

https://gcc.gnu.org/projects/cxx-status.html#cxx1z

-c++std c++11 more preferred chose.