I guess there are no common guidelines (at least, i've heard of none). Every company seem to have its own practices and recommendations. You may only rely on yourself and do whatever suits your current needs, i think.
Here's a link to the Google C++ Style Guide, if you haven't seen it already: https://google.github.io/styleguide/cppguide.html (they've got lots of ideas there, but i don't accept some of them, so it is a matter of choice)
Here's some other random guideline: http://geosoft.no/development/cppstyle.html
I guess you may take a look at those, but there is no general rule of thumb. Everything depends on your exact task.