let s:making = 0

command -nargs=* Make call s:make(<q-args>)

function s:make(args) abort

	if s:making
		if bufwinid(s:make_buf) == -1
			" show making buffer
			exe 'sbuffer' s:make_buf
			wincmd p
		else
			"hide making buffer
			exe printf('%d wincmd q', bufwinnr(s:make_buf))
		endif
		return
	endif

	" delete last result
	if exists('s:make_buf') && bufexists(s:make_buf)
		silent! exe 'bdelete' s:make_buf
	endif

	"spawn new make
	let cmd = &makeprg 
	if !empty(a:args)
		let cmd .= ' ' . a:args
	endif

	let options = {'close_cb': function('s:make_callback'), 'term_rows': 16}

	let s:make_buf = term_start(cmd, options)
	let s:making = 1

	wincmd p
endfunction

func s:make_callback(channel)

  " look, you can not get buffer content directly here.
  call timer_start(10, function('s:make_callback_impl'))
endfunction

function s:make_callback_impl(timer) abort

  exe 'cgetbuffer' s:make_buf

  " consider entry with num zero bufnr and lnum an error or warning
  let qfl = filter(getqflist(), {k,v -> v.bufnr != 0 && v.lnum != 0})

  if empty(qfl)
    echo "make successful"
  else
    echohl WarningMsg
    echom printf('found %d qf entries', len(qfl))
    echohl None
  endif

  let s:making = 0

endfunction