Re: [Boost-build] zlib and bipz2 not linking?

Subject: Re: [Boost-build] zlib and bipz2 not linking?
From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2018-09-07 14:50:28

AMDG

On 09/06/2018 09:43 PM, Kuhl, Brian via Boost-build wrote:
> Hi Experts,
> When cross compiling for VxWorks on Linux  ...
> In previous versions of Boost the presence of libz.a and libbz2.a were detected and linked into iostreams tests.
> But with v1.68 the libraries are not being added to the link line.
> Please see below for an example error.
> 
> The config-cache and the build console indicate that libz and bzip are being found, it's just not being used when required.
> 
> I'm having trouble deciphering ac.jam, so I was hopping someone could help me understand  how a dependency on /zlib//zlib is supposed to add -lz to the link line?
> And why it might not work in my case?
> 

  What's supposed to happen is that ac-library.construct
returns a target representing -lz.  When boost_iostreams
is built as a static library, it propagates this target
to its dependencies as a <library> usage requirement.
I would recommend --debug-building and/or --debug-generators,
but that just shows the dependency as <library>object(file-target)@NNN
which is not really useful.

  Okay, try building just one test target with
`--debug-building --debug-generators -n -d0`.
There are two things that you should be looking
for in the output.  First of all, there should
be two lines like this:

         Usage requirements for boost_iostreams:  ...
         Build properties:  ... <install-dependencies>off
<library>object(file-target)@4855 ...

If the <library> is missing, then that means that zlib is
not being passed to the boost_iostreams target.

The second line to look for is:
         Usage requirements from boost_iostreams:  <include>.
<library>object(file-target)@4855 <relevant>address-model ...

If there is no library here, then that means the problem
is in the propagation of static libraries.

> Many thanks,
> 
> Brian Kuhl
> Wind River
> 
> 
> . ./vxworks_env.sh &&  cd status   &&  \
>                     BOOST_TELNET_ADDR="localhost 20023"  \
>                     LAYER_SRC_PATH="yow-build62-lx:VSB/3pp/BOOST/boost_1_68_0" \
>                     PKG_SRC_BUILD_DIR="/yow-build62-lx2/bkuhl/work/VSB/3pp/BOOST/boost_1_68_0"  \
>                     VSB_LD_LIBRARY_PATH="yow-build62-lx:VSB/usr/root/llvm/bin;yow-build62-lx:VSB/usr/lib/common" \
> ../b2 -j1 --prefix=/yow-build62-lx2/bkuhl/work/VSB/usr/root --libdir=/yow-build62-lx2/bkuhl/work/VSB/usr/lib/common --includedir=/yow-build62-lx2/bkuhl/work/VSB/usr/h/public    toolset=clang-vxworks cross-compile=vxworks --reconfigure target-os=vxworks "variant=debug" address-model=64  static-only=on  "testing.launcher=./vxworks_boost_test_run.exp" "--limit-tests=iostreams|system" "--exclude-tests=coroutine2|function_types|functional|logic|rational" -d2
> Performing configuration checks
>     - default address-model    : 64-bit
>     - default architecture     : x86
>     - default address-model    : 64-bit
>     - default architecture     : x86
>     - symlinks supported       : yes
>     - BOOST_COMP_GNUC >= 4.3.0 : no
>     - zlib                     : yes
>     - bzip2                    : yes
>     - lzma                     : no
> <snip>
> 
> 
> clang-vxworks.link ../bin.v2/libs/iostreams/test/bzip2_test.test/clang-vxworks-4.2.1/debug/cross-compile-vxworks/static-only-on/bzip2_test.vxe
>     /yow-build62-lx2/bkuhl/vx7/compilers/llvm-6.0.0.2/LINUX386/bin/ldpentium -m elf_x86_64  -L"/yow-build62-lx2/bkuhl/work/VSB/usr/lib/common" -o "../bin.v2/libs/iostreams/test/bzip2_test.test/clang-vxworks-4.2.1/debug/cross-compile-vxworks/static-only-on/bzip2_test.vxe" /yow-build62-lx2/bkuhl/work/VSB/usr/lib/common//crt0.o "../bin.v2/libs/iostreams/test/bzip2_test.test/clang-vxworks-4.2.1/debug/cross-compile-vxworks/static-only-on/bzip2_test.o" "../bin.v2/libs/iostreams/build/clang-vxworks-4.2.1/debug/cross-compile-vxworks/static-only-on/libboost_iostreams.a" "../bin.v2/libs/test/build/clang-vxworks-4.2.1/debug/cross-compile-vxworks/static-only-on/libboost_unit_test_framework.a" "../bin.v2/libs/filesystem/build/clang-vxworks-4.2.1/debug/cross-compile-vxworks/static-only-on/libboost_filesystem.a" "../bin.v2/libs/timer/build/clang-vxworks-4.2.1/debug/cross-compile-vxworks/static-only-on/libboost_timer.a" "../bin.v2/libs/chrono/build/clang-vxworks-4.2.1/debug/cross-compile-vxworks/static-only-on/libboost_chrono.a" "../bin.v2/libs/system/build/clang-vxworks-4.2.1/debug/cross-compile-vxworks/static-only-on/libboost_system.a" --start-group -lunix -lnet  -lc  -lc_internal  -lllvm  -lcplusplus  -lllvmcplus  -ldl  -lsyscall      --end-group  --defsym __wrs_rtp_base=0x200000000 -u __tls__  -u __wr_need_frame_add -T/yow-build62-lx2/bkuhl/vx7/helix/guests/vxworks-7/build/tool/llvm_2016_04/usr/ldscript.vxe.x86-64   -L/yow-build62-lx2/bkuhl/work/VSB/usr/lib/common -z common-page-size=8192  -static
> ../bin.v2/libs/iostreams/build/clang-vxworks-4.2.1/debug/cross-compile-vxworks/static-only-on/libboost_iostreams.a(bzip2.o): In function `boost::iostreams::detail::bzip2_base::end(bool)':
> /yow-build62-lx2/bkuhl/work/VSB/3pp/BOOST/boost_1_68_0/status/../libs/iostreams/src/bzip2.cpp:121: undefined reference to `BZ2_bzCompressEnd'
> <snip>