Help building one module with cross-compiler

From: Adrian C (adrian_att_at_[hidden])
Date: 2019-08-24 18:05:04

 Hi,

I am trying to build boost module "log" on a raspberry PI as a dependency to another project. The RPI runs out of virtual memory during the build process, although I do limit building to just log (I think it builds some dependencies though).
So I decided to cross compile it on a x86 machine with plenty of resources. I followed the instructions and built using:
BUILD_CXXFLAGS="-std=gnu++11 -pthread" BUILD_CXX=arm-linux-gnueabihf-gcc ./bootstrap.sh --with-libraries=log --with-toolset=cross-cxx

The build fails with the bootstrap.log showing the content below. Your advice is appreciated.
thank you
ubuntu_at_ryu:~/arm-toolkit/boost_1_71_0$ cat bootstrap.log######### Using 'cross-cxx' toolset.######arm-linux-gnueabihf-gcc --versionarm-linux-gnueabihf-gcc (crosstool-NG linaro-1.13.1+bzr2650 - Linaro GCC 2014.03) 4.8.3 20140303 (prerelease)Copyright (C) 2013 Free Software Foundation, Inc.This is free software; see the source for copying conditions. Â There is NOwarranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
######arm-linux-gnueabihf-gcc -std=gnu++11 -pthread -DNDEBUG builtins.cpp class.cpp command.cpp compile.cpp constants.cpp cwd.cpp debug.cpp debugger.cpp execcmd.cpp filesys.cpp frames.cpp function.cpp glob.cpp hash.cpp hcache.cpp hdrmacro.cpp headers.cpp jam.cpp jambase.cpp jamgram.cpp lists.cpp make.cpp make1.cpp md5.cpp mem.cpp modules.cpp native.cpp object.cpp option.cpp output.cpp parse.cpp pathsys.cpp regexp.cpp rules.cpp scan.cpp search.cpp strings.cpp subst.cpp sysinfo.cpp timestamp.cpp variable.cpp w32_getreg.cpp modules/order.cpp modules/path.cpp modules/property-set.cpp modules/regex.cpp modules/sequence.cpp modules/set.cpp execunix.cpp fileunix.cpp pathunix.cpp -o b2/tmp/ccFB5qkl.o: In function `(anonymous namespace)::std_thread_hardware_concurrency()':sysinfo.cpp:(.text+0x118): undefined reference to `std::thread::hardware_concurrency()'collect2: error: ld returned 1 exit status