ale/ale_linters/cpp/gcc.vim

" Author: geam <mdelage@student.42.fr>
" Description: gcc linter for cpp files

" Set this option to change the GCC options for warnings for C.
if !exists('g:ale_cpp_gcc_options')
    " added c++14 standard support
    " POSIX thread and standard c++ thread and atomic library Linker
    " let g:ale_cpp_gcc_options = '-std=c++1z' for c++17
    " for previous version and default, you can just use
    " let g:ale_cpp_gcc_options = '-Wall'
    " for more see man pages of gcc
    " $ man g++
    " make sure g++ in your $PATH
    " Add flags according to your requirements
    let g:ale_cpp_gcc_options = '-std=c++14 -Wall'
endif

function! ale_linters#cpp#gcc#GetCommand(buffer) abort
    " -iquote with the directory the file is in makes #include work for
    "  headers in the same directory.
    return 'gcc -S -x c++ -fsyntax-only '
    \   . '-iquote ' . fnameescape(fnamemodify(bufname(a:buffer), ':p:h'))
    \   . ' ' . ale#Var(a:buffer, 'cpp_gcc_options') . ' -'
endfunction

call ale#linter#Define('cpp', {
\   'name': 'g++',
\   'output_stream': 'stderr',
\   'executable': 'g++',
\   'command_callback': 'ale_linters#cpp#gcc#GetCommand',
\   'callback': 'ale#handlers#gcc#HandleGCCFormat',
\})