Why does host-boost contain only a minimal selection?

I have a system set up where I build both natively (for running unit tests) and cross. My application uses libboost (package/boost) and fails to build natively because the linker can't find libboost-filesystem.so. I investigated the issue and find the following in package/boost/boost.mk:

# keep host variant as minimal as possible
HOST_BOOST_FLAGS = --without-icu --without-libraries=$(subst
$(space),$(comma),atomic chrono context coroutine date_time exception
filesystem graph graph_parallel iostreams locale log math mpi
program_options python random regex serialization signals system test
thread timer wave)

I guess this is why my host-boost does not contain the filesystem part. What is the reason for removing almost all parts of host-boost when the individual selection flags are already present and used correctly for the cross build?

Hello Anders,

Quoted 12 lines · Anders Norman

I have a system set up where I build both natively (for running unit tests) and cross. My application uses libboost (package/boost) and fails to build natively because the linker can't find libboost-filesystem.so. I investigated the issue and find the following in package/boost/boost.mk:

# keep host variant as minimal as possible
HOST_BOOST_FLAGS = --without-icu --without-libraries=$(subst
$(space),$(comma),atomic chrono context coroutine date_time exception
filesystem graph graph_parallel iostreams locale log math mpi
program_options python random regex serialization signals system test
thread timer wave)

Quoted 4 lines

I guess this is why my host-boost does not contain the filesystem part. What is the reason for removing almost all parts of host-boost when the individual selection flags are already present and used correctly for the cross build?

The point of most host-* packages is simply to allow building tools that are needed to build things for the target. So if a minimal configuration of Boost is sufficient to build the Boost things on the host that are needed to build the things for the target, then we prefer to have such a minimal configuration that is faster to build.

We do not intend to have the configuration of all host packages match the one of the target packages.

If you want to run your unit tests natively, then you should have a separate Buildroot configuration targetting x86/x86-64, and therefore use the target Boost.