Cross compiling boost for Arm (armhf) fails with unknown in module "warnings-feature"

Question

Following the Boost "Cross-compilation" instructions here ,

Having already run bootstrap.sh , and created a local, native b2 .

And using a user-config.jam of:

using gcc : arm :arm-linux-gnueabihf-g++ ;

Kicking off the build:

./b2 toolset=gcc-arm target-os=linux

Boost's b2 spits out a bunch of error messages, and halts:

username@ubuntu:~/Code/boost_1_81_0$ ./b2 toolset=gcc-arm target-os=linux
/home/username/Code/boost_1_81_0/tools/build/src/util/numbers.jam:23: in numbers.check from module numbers
error: arm in arm
error: is not a number
/home/username/Code/boost_1_81_0/tools/build/src/build/version.jam:110: in version.version-compatible from module version
/home/username/Code/boost_1_81_0/tools/build/src/tools/common.jam:1132: in common.find-compiler from module common
/home/username/Code/boost_1_81_0/tools/build/src/tools/gcc.jam:165: in gcc.init from module gcc
/home/username/Code/boost_1_81_0/tools/build/src/build/toolset.jam:44: in toolset.using from module toolset
/home/username/Code/boost_1_81_0/tools/build/src/build-system.jam:543: in process-explicit-toolset-requests from module build-system
/home/username/Code/boost_1_81_0/tools/build/src/build-system.jam:610: in load from module build-system
/home/username/Code/boost_1_81_0/tools/build/src/kernel/modules.jam:294: in import from module modules
/home/username/Code/boost_1_81_0/tools/build/src/kernel/bootstrap.jam:135: in module scope from module

Obviously it doesn't expect the values the instructions suggest.

Is there any way forward?

Answer 1

I am not sure about what exactly went wrong, but a complete, working procedure for cross-compiling boost for arm-linux-gnueabihf on Ubuntu 22.04 would be:

# Retrieve/install cross-compiler.
wget  https://developer.arm.com/-/media/Files/downloads/gnu/12.2.rel1/binrel/arm-gnu-toolchain-12.2.rel1-x86_64-arm-none-linux-gnueabihf.tar.xz
tar Jxf arm-gnu-toolchain-12.2.rel1-x86_64-arm-none-linux-gnueabihf.tar.xz
export CROSS_COMPILE=$(pwd)/arm-gnu-toolchain-12.2.rel1-x86_64-arm-none-linux-gnueabihf/bin/arm-none-linux-gnueabihf-

# Retrieve/install boost source code.
wget https://boostorg.jfrog.io/artifactory/main/release/1.81.0/source/boost_1_81_0.tar.bz2
tar jxf boost_1_81_0.tar.bz2

# Build boost
cd boost_1_81_0
echo "using gcc : arm : ${CROSS_COMPILE}g++ ;" > user_config.jam
./bootstrap.sh --prefix=$(pwd)/boost-1.81.0-arm-none-linux-gnueabihf
./b2 install toolset=gcc-arm link=static cxxflags=-fPIC --with-filesystem --with-test --with-log --with-program_options -j32 --user-config=user_config.jam

After the compilation ends, the compilation artifacts should reside in directory boost_1_81_0/boost-1.81.0-arm-none-linux-gnueabihf .