what is cross compilation
The programs we compile in Linux using the built-in gcc and g++ compilers are for the X86 architecture. Most of our development boards are development boards of ARM or other architectures, and we need to compile programs for other architectures.
So what exactly is cross compilation?
In fact, it is to compile the code on other platforms on our PC (X86), which is called cross-compilation.
If you want to compile programs executable on other platforms, you need to use different compilers, because different compilers have different instruction sets.
about
There are many cross compilers, this time we use a cross compilation tool provided by linaro company.
Address: http://releases.linaro.org/
Direct link:
http://releases.linaro.org/components/toolchain/binaries/4.9-2017.01/arm-linux-gnueabi/
1. After downloading, unzip it:
tar -xvf gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabi.tar.xz
2. Copy the entire unzipped directory to the place you want to store it
I put it in my unified management place
mv gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabi ~/soft/linux_tools/
zh@zh-lpc:~/soft/linux_tools$ pwd
/home/zh/soft/linux_tools
zh@zh-lpc:~/soft/linux_tools$ ls
gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabi
zh@zh-lpc:~/soft/linux_tools$
3. Test whether it can be run
After entering the bin directory, execute ./arm-linux-gnueabi-gcc -v to view the version information. If it is successful, it is OK.
zh@zh-lpc:~/soft/linux_tools$
zh@zh-lpc:~/soft/linux_tools$ cd gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabi/
zh@zh-lpc:~/soft/linux_tools/gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabi$ cd bin/
zh@zh-lpc:~/soft/linux_tools/gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabi/bin$
zh@zh-lpc:~/soft/linux_tools/gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabi/bin$
zh@zh-lpc:~/soft/linux_tools/gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabi/bin$ pwd
/home/zh/soft/linux_tools/gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabi/bin
zh@zh-lpc:~/soft/linux_tools/gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabi/bin$ ls
arm-linux-gnueabi-addr2line arm-linux-gnueabi-cpp arm-linux-gnueabi-gcc-ar arm-linux-gnueabi-gfortran arm-linux-gnueabi-objcopy arm-linux-gnueabi-strings
arm-linux-gnueabi-ar arm-linux-gnueabi-elfedit arm-linux-gnueabi-gcc-nm arm-linux-gnueabi-gprof arm-linux-gnueabi-objdump arm-linux-gnueabi-strip
arm-linux-gnueabi-as arm-linux-gnueabi-g++ arm-linux-gnueabi-gcc-ranlib arm-linux-gnueabi-ld arm-linux-gnueabi-ranlib gdbserver
arm-linux-gnueabi-c++ arm-linux-gnueabi-gcc arm-linux-gnueabi-gcov arm-linux-gnueabi-ld.bfd arm-linux-gnueabi-readelf runtest
arm-linux-gnueabi-c++filt arm-linux-gnueabi-gcc-4.9.4 arm-linux-gnueabi-gdb arm-linux-gnueabi-nm arm-linux-gnueabi-size
zh@zh-lpc:~/soft/linux_tools/gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabi/bin$
zh@zh-lpc:~/soft/linux_tools/gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabi/bin$ ./arm-linux-gnueabi-gcc -v
使用内建 specs。
COLLECT_GCC=./arm-linux-gnueabi-gcc
COLLECT_LTO_WRAPPER=/home/zh/soft/linux_tools/gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabi/bin/../libexec/gcc/arm-linux-gnueabi/4.9.4/lto-wrapper
目标：arm-linux-gnueabi
配置为：/home/tcwg-buildslave/workspace/tcwg-make-release/label/docker-trusty-amd64-tcwg-build/target/arm-linux-gnueabi/snapshots/gcc-linaro-4.9-2017.01/configure SHELL=/bin/bash --with-mpc=/home/tcwg-buildslave/workspace/tcwg-make-release/label/docker-trusty-amd64-tcwg-build/target/arm-linux-gnueabi/_build/builds/destdir/x86_64-unknown-linux-gnu --with-mpfr=/home/tcwg-buildslave/workspace/tcwg-make-release/label/docker-trusty-amd64-tcwg-build/target/arm-linux-gnueabi/_build/builds/destdir/x86_64-unknown-linux-gnu --with-gmp=/home/tcwg-buildslave/workspace/tcwg-make-release/label/docker-trusty-amd64-tcwg-build/target/arm-linux-gnueabi/_build/builds/destdir/x86_64-unknown-linux-gnu --with-gnu-as --with-gnu-ld --disable-libmudflap --enable-lto --enable-objc-gc --enable-shared --without-included-gettext --enable-nls --disable-sjlj-exceptions --enable-gnu-unique-object --enable-linker-build-id --disable-libstdcxx-pch --enable-c99 --enable-clocale=gnu --enable-libstdcxx-debug --enable-long-long --with-cloog=no --with-ppl=no --with-isl=no --disable-multilib --with-float=soft --with-mode=thumb --with-tune=cortex-a9 --with-arch=armv7-a --with-fpu=vfpv3-d16 --enable-threads=posix --enable-multiarch --enable-libstdcxx-time=yes --with-build-sysroot=/home/tcwg-buildslave/workspace/tcwg-make-release/label/docker-trusty-amd64-tcwg-build/target/arm-linux-gnueabi/_build/sysroots/arm-linux-gnueabi --with-sysroot=/home/tcwg-buildslave/workspace/tcwg-make-release/label/docker-trusty-amd64-tcwg-build/target/arm-linux-gnueabi/_build/builds/destdir/x86_64-unknown-linux-gnu/arm-linux-gnueabi/libc --enable-checking=release --disable-bootstrap --enable-languages=c,c++,fortran,lto --build=x86_64-unknown-linux-gnu --host=x86_64-unknown-linux-gnu --target=arm-linux-gnueabi --prefix=/home/tcwg-buildslave/workspace/tcwg-make-release/label/docker-trusty-amd64-tcwg-build/target/arm-linux-gnueabi/_build/builds/destdir/x86_64-unknown-linux-gnu
线程模型：posix
gcc 版本 4.9.4 (Linaro GCC 4.9-2017.01)
zh@zh-lpc:~/soft/linux_tools/gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabi/bin$
4. Configure environment variables
If you want to be able to execute it anywhere directly like the gcc command that comes with the system, you need to configure environment variables.
4-1, remember the following directory
/home/zh/soft/linux_tools/gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabi/bin
zh@zh-lpc:~/soft/linux_tools/gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabi/bin$ pwd
/home/zh/soft/linux_tools/gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabi/bin
zh@zh-lpc:~/soft/linux_tools/gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabi/bin$
4-2. Open the configuration file
We can choose to configure all users in the system, then open: /etc/profile
If you want to configure a specific user, you can open the user directory:
vim ~/.profile
vim ~/.bashrc
Wait, it's all possible.
Open:
zh@zh-lpc:~$ vim ~/.bashrc
zh@zh-lpc:~$
join in:
export ARCH=arm
export CROSS_COMPILE=arm-linux-gnueabihf-
export PATH=$PATH:/home/zh/soft/linux_tools/gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabi/bin
Make it work:
zh@zh-lpc:~$ source ~/.bashrc
zh@zh-lpc:~$
test:
zh@zh-lpc:~$
zh@zh-lpc:~$ arm-linux-gnueabi
arm-linux-gnueabi-addr2line arm-linux-gnueabi-gcc-ar arm-linux-gnueabihf-c++ arm-linux-gnueabihf-gcc-ranlib arm-linux-gnueabihf-objcopy arm-linux-gnueabi-objcopy
arm-linux-gnueabi-ar arm-linux-gnueabi-gcc-nm arm-linux-gnueabihf-c++filt arm-linux-gnueabihf-gcov arm-linux-gnueabihf-objdump arm-linux-gnueabi-objdump
arm-linux-gnueabi-as arm-linux-gnueabi-gcc-ranlib arm-linux-gnueabihf-cpp arm-linux-gnueabihf-gcov-tool arm-linux-gnueabihf-ranlib arm-linux-gnueabi-ranlib
arm-linux-gnueabi-c++ arm-linux-gnueabi-gcov arm-linux-gnueabihf-dwp arm-linux-gnueabihf-gdb arm-linux-gnueabihf-readelf arm-linux-gnueabi-readelf
arm-linux-gnueabi-c++filt arm-linux-gnueabi-gdb arm-linux-gnueabihf-elfedit arm-linux-gnueabihf-gfortran arm-linux-gnueabihf-size arm-linux-gnueabi-size
arm-linux-gnueabi-cpp arm-linux-gnueabi-gfortran arm-linux-gnueabihf-g++ arm-linux-gnueabihf-gprof arm-linux-gnueabihf-strings arm-linux-gnueabi-strings
arm-linux-gnueabi-elfedit arm-linux-gnueabi-gprof arm-linux-gnueabihf-gcc arm-linux-gnueabihf-ld arm-linux-gnueabihf-strip arm-linux-gnueabi-strip
arm-linux-gnueabi-g++ arm-linux-gnueabihf-addr2line arm-linux-gnueabihf-gcc-6.2.1 arm-linux-gnueabihf-ld.bfd arm-linux-gnueabi-ld
arm-linux-gnueabi-gcc arm-linux-gnueabihf-ar arm-linux-gnueabihf-gcc-ar arm-linux-gnueabihf-ld.gold arm-linux-gnueabi-ld.bfd
arm-linux-gnueabi-gcc-4.9.4 arm-linux-gnueabihf-as arm-linux-gnueabihf-gcc-nm arm-linux-gnueabihf-nm arm-linux-gnueabi-nm
zh@zh-lpc:~$ arm-linux-gnueabi-gcc -v
使用内建 specs。
COLLECT_GCC=arm-linux-gnueabi-gcc
COLLECT_LTO_WRAPPER=/home/zh/soft/linux_tools/gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabi/bin/../libexec/gcc/arm-linux-gnueabi/4.9.4/lto-wrapper
目标：arm-linux-gnueabi
配置为：/home/tcwg-buildslave/workspace/tcwg-make-release/label/docker-trusty-amd64-tcwg-build/target/arm-linux-gnueabi/snapshots/gcc-linaro-4.9-2017.01/configure SHELL=/bin/bash --with-mpc=/home/tcwg-buildslave/workspace/tcwg-make-release/label/docker-trusty-amd64-tcwg-build/target/arm-linux-gnueabi/_build/builds/destdir/x86_64-unknown-linux-gnu --with-mpfr=/home/tcwg-buildslave/workspace/tcwg-make-release/label/docker-trusty-amd64-tcwg-build/target/arm-linux-gnueabi/_build/builds/destdir/x86_64-unknown-linux-gnu --with-gmp=/home/tcwg-buildslave/workspace/tcwg-make-release/label/docker-trusty-amd64-tcwg-build/target/arm-linux-gnueabi/_build/builds/destdir/x86_64-unknown-linux-gnu --with-gnu-as --with-gnu-ld --disable-libmudflap --enable-lto --enable-objc-gc --enable-shared --without-included-gettext --enable-nls --disable-sjlj-exceptions --enable-gnu-unique-object --enable-linker-build-id --disable-libstdcxx-pch --enable-c99 --enable-clocale=gnu --enable-libstdcxx-debug --enable-long-long --with-cloog=no --with-ppl=no --with-isl=no --disable-multilib --with-float=soft --with-mode=thumb --with-tune=cortex-a9 --with-arch=armv7-a --with-fpu=vfpv3-d16 --enable-threads=posix --enable-multiarch --enable-libstdcxx-time=yes --with-build-sysroot=/home/tcwg-buildslave/workspace/tcwg-make-release/label/docker-trusty-amd64-tcwg-build/target/arm-linux-gnueabi/_build/sysroots/arm-linux-gnueabi --with-sysroot=/home/tcwg-buildslave/workspace/tcwg-make-release/label/docker-trusty-amd64-tcwg-build/target/arm-linux-gnueabi/_build/builds/destdir/x86_64-unknown-linux-gnu/arm-linux-gnueabi/libc --enable-checking=release --disable-bootstrap --enable-languages=c,c++,fortran,lto --build=x86_64-unknown-linux-gnu --host=x86_64-unknown-linux-gnu --target=arm-linux-gnueabi --prefix=/home/tcwg-buildslave/workspace/tcwg-make-release/label/docker-trusty-amd64-tcwg-build/target/arm-linux-gnueabi/_build/builds/destdir/x86_64-unknown-linux-gnu
线程模型：posix
gcc 版本 4.9.4 (Linaro GCC 4.9-2017.01)
zh@zh-lpc:~$
Then configure other versions as well.