Cannot build darling

I was trying to install darling on Ubuntu 22.04.2 LTS. When I run the following command:

:~/darling/build$ cmake ..

The following error occured:

-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - failed
-- Check for working CXX compiler: /usr/bin/clang++
-- Check for working CXX compiler: /usr/bin/clang++ - broken
CMake Error at /usr/share/cmake-3.22/Modules/CMakeTestCXXCompiler.cmake:62 (message):
  The C++ compiler

    "/usr/bin/clang++"

  is not able to compile a simple test program.

  It fails with the following output:

    Change Dir: /home/faisalmustafa/darling/build/CMakeFiles/CMakeTmp
    
    Run Build Command(s):/usr/bin/gmake -f Makefile cmTC_c6302/fast && /usr/bin/gmake  -f CMakeFiles/cmTC_c6302.dir/build.make CMakeFiles/cmTC_c6302.dir/build
    gmake[1]: Entering directory '/home/faisalmustafa/darling/build/CMakeFiles/CMakeTmp'
    Building CXX object CMakeFiles/cmTC_c6302.dir/testCXXCompiler.cxx.o
    /usr/bin/clang++    -MD -MT CMakeFiles/cmTC_c6302.dir/testCXXCompiler.cxx.o -MF CMakeFiles/cmTC_c6302.dir/testCXXCompiler.cxx.o.d -o CMakeFiles/cmTC_c6302.dir/testCXXCompiler.cxx.o -c /home/faisalmustafa/darling/build/CMakeFiles/CMakeTmp/testCXXCompiler.cxx
    Linking CXX executable cmTC_c6302
    /usr/bin/cmake -E cmake_link_script CMakeFiles/cmTC_c6302.dir/link.txt --verbose=1
    /usr/bin/clang++ -rdynamic CMakeFiles/cmTC_c6302.dir/testCXXCompiler.cxx.o -o cmTC_c6302 
    /usr/bin/ld: cannot find -lstdc++: No such file or directory
    clang: error: linker command failed with exit code 1 (use -v to see invocation)
    gmake[1]: *** [CMakeFiles/cmTC_c6302.dir/build.make:100: cmTC_c6302] Error 1
    gmake[1]: Leaving directory '/home/faisalmustafa/darling/build/CMakeFiles/CMakeTmp'
    gmake: *** [Makefile:127: cmTC_c6302/fast] Error 2
    
    
  CMake will not be able to correctly generate this project.
Call Stack (most recent call first):
  CMakeLists.txt:44 (project)


-- Configuring incomplete, errors occurred!
See also "/home/faisalmustafa/darling/build/CMakeFiles/CMakeOutput.log".
See also "/home/faisalmustafa/darling/build/CMakeFiles/CMakeError.log". 

How do you think I can fix this problem?

Thank you very much for your help.

This seems to be an issue that arises when a higher version of gcc is present on your system than of g++; clang++ detects and chooses the highest version of gcc (in your case, gcc-12) and then fails to link g++ programs because the /usr/lib/gcc/x86_64-linux-gnu/12/ directory lacks the corresponding C++ standard libraries.

The issue is also reported in After updating GCC, Clang can't find libstdc++ anymore. I can reproduce the error myself on 22.04 where

$ apt policy gcc g++
gcc:
  Installed: 4:11.2.0-1ubuntu1
  Candidate: 4:11.2.0-1ubuntu1
  Version table:
 *** 4:11.2.0-1ubuntu1 500
        500 http://archive.ubuntu.com/ubuntu jammy/main amd64 Packages
        100 /var/lib/dpkg/status
g++:
  Installed: 4:11.2.0-1ubuntu1
  Candidate: 4:11.2.0-1ubuntu1
  Version table:
 *** 4:11.2.0-1ubuntu1 500
        500 http://archive.ubuntu.com/ubuntu jammy/main amd64 Packages
        100 /var/lib/dpkg/status

but gcc-12 is present apparently as a dependency of the dkms package:

$ aptitude why gcc-12
i   dkms Depends gcc-12

(perhaps because the current kernel was built with gcc-12?). So clang++ detects and prefers it:

$ clang++ -v -o hello hello.cpp 2>&1 | grep ^Found
Found candidate GCC installation: /usr/bin/../lib/gcc/x86_64-linux-gnu/10
Found candidate GCC installation: /usr/bin/../lib/gcc/x86_64-linux-gnu/11
Found candidate GCC installation: /usr/bin/../lib/gcc/x86_64-linux-gnu/12

I'm not sure the best solution; more recent versions of clang provide a --gcc-install-dir option but that is not present in clang-14. One option that appears to work is to pass the gcc-11 library path as a linker option:

clang++ -Wl,-L/usr/lib/gcc/x86_64-linux-gnu/11 -o hello hello.cpp

(or equivalently by exporting LIBRARY_PATH=/usr/lib/gcc/x86_64-linux-gnu/11 in your build environment). I'm slightly hesitant to recommend it in case that introduces inconsistencies between header files and libraries. I guess another option is to manually install g++-12 on your system.

You are missing lstdc++. Try sudo apt install libstdc++-11-dev.