I recently got Syntastic (got it by vim-plug, Plug 'vim-syntastic/syntastic') and it works for c++ and c.
Example:
What I used:
let g:syntastic_cpp_checkers = ['gcc']
And when I use Python or HTML or CSS.
Example(with Python):
What I used:
let g:syntastic_python_checkers = ['bandit', 'python']
And same problem is with other languages.
Edit:
:SyntasticInfo for python
Syntastic version: 3.9.0-9 (Vim 704, Linux)
Info for filetype: python
Global mode: active
Filetype python is active
The current file will be checked automatically
Available checker: python
Currently enabled checker: python