This tool shall enable a user to run compilation commands from a compile_commands.json file without messing with the original build tool.

Applications may be:

• using a different compiler (e.g. clang++ instead of g++)

go run github.com/pseyfert/compile_commands_json_executer --cmd /path/to/clang++

• add compiler arguments

go run github.com/pseyfert/compile_commands_json_executer --cmd /path/to/clang++ --extra-arg=--gcc-toolchain=--gcc-toolchain=/cvmfs/lhcb.cern.ch/lib/lcg/releases/gcc/7.3.0/x86_64-centos7

• run other clang tools (kythe, include-what-you-use)

go run github.com/pseyfert/compile_commands_json_executer --cmd /opt/kythe/extractors/cxx_extractor --env LD_LIBRARY_PATH=/cvmfs/lhcb.cern.ch/lib/lcg/releases/clang/8.0.0/x86_64-centos7/lib64:/cvmfs/lhcb.cern.ch/lib/lcg/releases/gcc/8.2.0/x86_64-centos7/lib64:/cvmfs/lhcb.cern.ch/lib/lcg/releases/binutils/2.30/x86_64-centos7/lib${LD_LIBRARY_PATH:+:${LD_LIBRARY_PATH}} --extra-arg=--gcc-toolchain=/cvmfs/lhcb.cern.ch/lib/lcg/releases/gcc/8.2.0/x86_64-centos7

• or just disable compilation and only run preprocessors

go run github.com/pseyfert/compile_commands_json_executer --remove-filter='-c' --append='-E'

what's there and what isn't

what's there

• concurrency: -j 4 to run with 4 thread
• relative path handling: the working directory of the compiler call shall be the one specified in the compilation database. Relative paths therein should just work.
• limitted compiler launcher tool detection: when using a compiler launcher in the database like ccache g++, the combination of them is detected as "executable". It won't be replaced to cxx_extractor g++ but instead to cxx_extractor.
• many arguments can occur repeatedly, such as --extra-arg and --extra-arg-before to add multiple arguments (they maintain the order in which they appear, i.e. the first --extra-arg-before will be the first argument)
• --trace will write a json file that can be opened with the chrome webbrowser on the chrome://tracing page to visualize which processes launch when.
• see also the output of --help

what's not there

• multi word argument treatment: file name replacements for output files (e.g. -o /some/outfile or -MF /some/other) can not be done as the replace and remove-filter options go through the command line word by word and can't jump over the space after -o
• compiler launchers for the replacement executable (i.e. --cmd="ccache clang++" won't work). But they can be worked around with --cmd="ccache" --extra-arg-before "clang++"