Problems linking against xDot library

Questions » Problems linking against xDot library

6 years, 5 months ago.

I just tried the following steps:

    mbed import http://mbed.org/teams/MultiTech/code/Dot-Examples/
    cd Dot-Examples/
    mbed add http://mbed.org/teams/MultiTech/code/libxDot-mbed5/
    mbed compile -m xdot_l151cc -t GCC_ARM

And I'm getting a link error:

    Scan: FEATURE_STORAGE
    Scan: env
    Scan: mbed
    Link: Dot-Examples
    ./BUILD/xdot_l151cc/GCC_ARM/examples/src/dot_util.o: In function `join_network()':
    dot_util.cpp:(.text._Z12join_networkv+0x3e): undefined reference to `mDot::getReturnCodeString[abi:cxx11](long const&)'
    ./BUILD/xdot_l151cc/GCC_ARM/examples/src/dot_util.o: In function `sleep_wake_rtc_or_interrupt(bool)':    
    dot_util.cpp:(.text._Z27sleep_wake_rtc_or_interruptb+0x5e): undefined reference to `mDot::pinName2Str[abi:cxx11](PinName)'
    ./BUILD/xdot_l151cc/GCC_ARM/examples/src/dot_util.o: In function `send_data(std::vector<unsigned char, std::allocator<unsigned char> >)':
    dot_util.cpp:(.text._Z9send_dataSt6vectorIhSaIhEE+0x42): undefined reference to `mDot::getReturnCodeString[abi:cxx11](long           const&)'
    [snip]

Is this supposed to work? Compilation succeeds on the online compiler.

Thanks!

Question relating to:

MultiTech

MultiTech's official mbed team.

1 Answer

6 years, 5 months ago.

Apparently libxDot was compiled with an older version of C++. Details about the problem here: https://gcc.gnu.org/onlinedocs/libstdc++/manual/using_dual_abi.html

I was able to work around this by compiling Dot-Examples with the following macro

-D_GLIBCXX_USE_CXX11_ABI=0

This is the profile.json that I used:

{
    "GCC_ARM": {
        "common": ["-c", "-Wall", "-Wextra",
                   "-Wno-unused-parameter", "-Wno-missing-field-initializers",
                   "-fmessage-length=0", "-fno-exceptions", "-fno-builtin",
                   "-ffunction-sections", "-fdata-sections", "-funsigned-char",
                   "-MMD", "-fno-delete-null-pointer-checks",
                   "-fomit-frame-pointer", "-Os"],
        "asm": ["-x", "assembler-with-cpp"],
        "c": ["-std=gnu99"],
        "cxx": ["-std=c++98", "-fno-rtti", "-Wvla", "-D_GLIBCXX_USE_CXX11_ABI=0"],
        "ld": ["-Wl,--gc-sections", "-Wl,--wrap,main", "-Wl,--wrap,_malloc_r",
               "-Wl,--wrap,_free_r", "-Wl,--wrap,_realloc_r",
               "-Wl,--wrap,_calloc_r", "-Wl,--wrap,exit", "-Wl,--wrap,atexit"]
    }
}

and compiling as...

mbed compile -m xdot_l151cc -t GCC_ARM --profile profile.json

Accepted Answer

I had this same problem, and this solution worked. I also needed to add -Wl,- -allow-multiple-definition to the ld (linker) options to suppress errors about duplicate definitions of Mbed functions. (Remove the space in - -allow if you copy/paste this; the correct version doesn't render properly in this forum.) MultiTech really needs to fix their library.

posted by Adam Haun 05 Feb 2018

Assigned to Javier Cardona 6 years, 5 months ago.

This means that the question has been accepted and is being worked on.

Javier Cardona

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6 years, 5 months ago.