Cross-Compile for Raspberry pi opencv linking problems - linux

Question

(Sorry for bad English, I'm German)
Hello programmers,
I'm desperately trying to cross compile a program (using OpenCV) on my linux(fedora) x86_x64 laptop for a linux(raspian) Raspberry pi 3.
I'm following this tutorial (https://solderspot.wordpress.com/2016/02/04/cross-compiling-for-raspberry-pi-part-ii/) and a simple std::cout << "test\n"; program compiles and works fine with the following CMakeLists.txt:
cmake_minimum_required (VERSION 2.8)
project (CVS)
find_package(OpenCV REQUIRED)
SET(COMPILE_DEFINITIONS -Werror)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
add_definitions(-DHOST_ROBO_DIR=/home/username/Dropbox/Roboter)
include_directories(SYSTEM ${PIROOT}/opt/vc/include ${PIROOT}/opt/vc/include/interface/vcos/pthreads ${PIROOT}/opt/vc/include/interface/vmcs_host/linux )
link_directories( ${PIROOT}/opt/vc/lib )
add_executable (CVS ../source/main.cpp)
The Problem comes with OpenCV...
If I use the CMakeLists.txt from above it generates (for obvious reasons) many "undefined reference" errors eg.: "undefined reference to `cv::waitKey(int)'"
If I add "target_link_libraries( CVS ${OpenCV_LIBS} )" or "target_link_libraries(CVS -lopencv_core)" to the CMakeLists.txt make produces the following error:
/home/username/pidev/piroot/usr/local/lib/libopencv_core.so: undefined reference to `std::__throw_out_of_range_fmt(char const*, ...)#GLIBCXX_3.4.20'
If I replace "SET(TOOLROOT ${PITOOLS}/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian-x64)" in ~/pidev/pi-toolchain.cmake with "SET(TOOLROOT ${PITOOLS}/arm-bcm2708/arm-rpi-4.9.3-linux-gnueabihf)" I got the following error:
[username#MSI-Linux msi]$ cmake -DCMAKE_TOOLCHAIN_FILE=~/pidev/pi-toolchain.cmake .
-- The C compiler identification is GNU 4.9.3
-- The CXX compiler identification is GNU 4.9.3
-- Check for working C compiler: /home/username/pidev/pitools/arm-bcm2708/arm-rpi-4.9.3-linux-gnueabihf/bin/arm-linux-gnueabihf-gcc
-- Check for working C compiler: /home/username/pidev/pitools/arm-bcm2708/arm-rpi-4.9.3-linux-gnueabihf/bin/arm-linux-gnueabihf-gcc -- broken
CMake Error at /usr/share/cmake/Modules/CMakeTestCCompiler.cmake:61 (message):
The C compiler
"/home/username/pidev/pitools/arm-bcm2708/arm-rpi-4.9.3-linux-gnueabihf/bin/arm-linux-gnueabihf-gcc"
is not able to compile a simple test program.
It fails with the following output:
Change Dir: /home/username/Dropbox/Roboter/raspySync/CVS/cvs5-6/msi/CMakeFiles/CMakeTmp
Run Build Command:"/usr/bin/gmake" "cmTC_b1abe/fast"
/usr/bin/gmake -f CMakeFiles/cmTC_b1abe.dir/build.make
CMakeFiles/cmTC_b1abe.dir/build
gmake[1]: Verzeichnis
„/home/username/Dropbox/Roboter/raspySync/CVS/cvs5-6/msi/CMakeFiles/CMakeTmp“
wird betreten
Building C object CMakeFiles/cmTC_b1abe.dir/testCCompiler.c.o
/home/username/pidev/pitools/arm-bcm2708/arm-rpi-4.9.3-linux-gnueabihf/bin/arm-linux-gnueabihf-gcc
--sysroot=/home/username/pidev/piroot
-Wl,-rpath-link,/home/username/pidev/piroot/opt/vc/lib
-Wl,-rpath-link,/home/username/pidev/piroot/lib/arm-linux-gnueabihf
-Wl,-rpath-link,/home/username/pidev/piroot/usr/lib/arm-linux-gnueabihf
-Wl,-rpath-link,/home/username/pidev/piroot/usr/local/lib -o
CMakeFiles/cmTC_b1abe.dir/testCCompiler.c.o -c
/home/username/Dropbox/Roboter/raspySync/CVS/cvs5-6/msi/CMakeFiles/CMakeTmp/testCCompiler.c
Linking C executable cmTC_b1abe
/usr/bin/cmake -E cmake_link_script CMakeFiles/cmTC_b1abe.dir/link.txt
--verbose=1
/home/username/pidev/pitools/arm-bcm2708/arm-rpi-4.9.3-linux-gnueabihf/bin/arm-linux-gnueabihf-gcc
--sysroot=/home/username/pidev/piroot
-Wl,-rpath-link,/home/username/pidev/piroot/opt/vc/lib
-Wl,-rpath-link,/home/username/pidev/piroot/lib/arm-linux-gnueabihf
-Wl,-rpath-link,/home/username/pidev/piroot/usr/lib/arm-linux-gnueabihf
-Wl,-rpath-link,/home/username/pidev/piroot/usr/local/lib
CMakeFiles/cmTC_b1abe.dir/testCCompiler.c.o -o cmTC_b1abe -rdynamic
/home/username/pidev/pitools/arm-bcm2708/arm-rpi-4.9.3-linux-gnueabihf/bin/../lib/gcc/arm-linux-gnueabihf/4.9.3/../../../../arm-linux-gnueabihf/bin/ld:
cannot find crt1.o: No such file or directory
/home/username/pidev/pitools/arm-bcm2708/arm-rpi-4.9.3-linux-gnueabihf/bin/../lib/gcc/arm-linux-gnueabihf/4.9.3/../../../../arm-linux-gnueabihf/bin/ld:
cannot find crti.o: No such file or directory
collect2: error: ld returned 1 exit status
CMakeFiles/cmTC_b1abe.dir/build.make:97: die Regel für Ziel
„cmTC_b1abe“ scheiterte
gmake[1]: *** [cmTC_b1abe] Fehler 1
gmake[1]: Verzeichnis
„/home/username/Dropbox/Roboter/raspySync/CVS/cvs5-6/msi/CMakeFiles/CMakeTmp“
wird verlassen
Makefile:126: die Regel für Ziel „cmTC_b1abe/fast“ scheiterte
gmake: *** [cmTC_b1abe/fast] Fehler 2
CMake will not be able to correctly generate this project.
Call Stack (most recent call first):
CMakeLists.txt:2 (project)
-- Configuring incomplete, errors occurred!
See also "/home/username/Dropbox/Roboter/raspySync/CVS/cvs5-6/msi/CMakeFiles/CMakeOutput.log".
See also "/home/username/Dropbox/Roboter/raspySync/CVS/cvs5-6/msi/CMakeFiles/CMakeError.log".
[username#MSI-Linux msi]$
I would be thankful if anyone could answer one of these questions:
- How can I cross-compile a program that uses OpenCV commands
- Why is there an "undefined reference to `std::__throw_out_of_range_fmt(char const*, ...)#GLIBCXX_3.4.20'" and a "The C compiler ... is not able to compile a simple test program."
- Would it be bad or REALLY bad style if I add a something like this in the program:
namespace std
{
void __throw_out_of_range_fmt(char const*, ...)
{
std::cout << "throw out of range error\n";
}
}
Heres my ~/pidev/pi-toolchain.cmake:
SET(CMAKE_SYSTEM_NAME Linux)
SET(CMAKE_SYSTEM_VERSION 1)
SET(DEVROOT $ENV{HOME}/pidev)
SET(PIROOT ${DEVROOT}/piroot)
SET(PITOOLS ${DEVROOT}/pitools)
SET(TOOLROOT ${PITOOLS}/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian-x64)
# specify the cross compiler
SET(CMAKE_C_COMPILER ${TOOLROOT}/bin/arm-linux-gnueabihf-gcc)
SET(CMAKE_CXX_COMPILER ${TOOLROOT}/bin/arm-linux-gnueabihf-g++)
SET(CMAKE_SYSROOT ${PIROOT})
SET(CMAKE_FIND_ROOT_PATH ${PIROOT})
# search for programs in the build host directories
SET(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
# for libraries and headers in the target directories
SET(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
SET(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
SET(FLAGS "-Wl,-rpath-link,${PIROOT}/opt/vc/lib -Wl,-rpath-link,${PIROOT}/lib/arm-linux-gnueabihf -Wl,-rpath-link,${PIROOT}/usr/lib/arm-linux-gnueabihf -Wl,-rpath-link,${PIROOT}/usr/local/lib")
UNSET(CMAKE_C_FLAGS CACHE)
UNSET(CMAKE_CXX_FLAGS CACHE)
SET(CMAKE_CXX_FLAGS ${FLAGS} CACHE STRING "" FORCE)
SET(CMAKE_C_FLAGS ${FLAGS} CACHE STRING "" FORCE)

Answer 1

The "cannot find crt1.o: No such file or directory"-error is a known problem with the "arm-rpi-4.9.3-linux-gnueabihf"-toolchain, see 4.9 toolchain issue #50.
The "`std::__throw_out_of_range_fmt(char const*, ...)#GLIBCXX_3.4.20'"-error is related to gcc 4.8, see std::__throw_out_of_range_fmt(char const*, …)#GLIBCXX_3.4.20'. I'm not quite sure why this happens to you, since I was able to build opencv with the "gcc-linaro-arm-linux-gnueabihf-raspbian-x64"-toolchain.
Maybe you have some luck with the way I did it: How do I cross compile OpenCV for the Raspberry Pi with additional modules (highgui…)
Example CMakeLists.txt
project(Test)
cmake_minimum_required(VERSION 3.2)
set(CMAKE_CXX_STANDARD 11)
aux_source_directory(. SRC_LIST)
find_package(OpenCV REQUIRED)
add_executable(${PROJECT_NAME} ${SRC_LIST})
target_link_libraries(${PROJECT_NAME} ${OpenCV_LIBS})
Invoke cmake like this:
cmake -D CMAKE_TOOLCHAIN_FILE=$CMAKE_TOOLCHAIN_FILE -D PIROOT=$MOUNT_DIR -D TOOLROOT=$TOOLCHAIN ..