switch statement exiting a void function

[Jonathan via Digitalmars-d-learn]

Here's the setup, I have a function

     void main { ... }

The main method parses input (via std.getopt) and calls one of 
three void-return-type functions.  The program's three options 
correspond to significantly different initialization options.

In the code we then have:

     enum RunOpt {opt1, opt2, opt3};

And the body of the function wants to do:

     RunOpt option;
     //parsing that results in, among other things option being 
initialized
     switch(option){
         case RunOpt.opt1: fun1(...);
         case RunOpt.opt2: fun2(...);
         default: fun3(...);
     }

When compiling, the error I get is

     Error: switch case fallthrough - use 'goto case;' if intended

This is not intended.  Note that calling "return;" after 
"funi(...)" makes everything work.  However, it feels like I'm 
doing something wrong here?