pop user values in C functions

[Marc Balmer <marc@...>]

... I am getting slightly confused from to much hacking, so in a function that creates new uservalues, can I just leave them on the stack?
Will Lua automatically remove/pop  excess values from the stock when the function returns (e.g. I create four temp uservalues and
one result that I actually need.  Then I return 1.  Will the four uservalues do any harm?