No warning in VB.NET when function has no return

Question

Some comments on Stack Overflow question Why doesn\'t the C# compiler stop properties from referring to themselves? regarding warnings got me thinking about old issues that

Answer 1

I just wasted seven hours about the same problem. In my case (using Visual Studio 2012) the compilation ended with a compilation error:

Error MSB3030: File "obj\x86 Debug\.exe" could not be copied, because the file was not found. (0, 0)

(The text was translated from the German error message, and I hope it's translated properly.)

Since that message didn't help, I reverted my project back to state where it compiled and finally tracked it down to something similar to the following:

Function SomeFunction() as Boolean
  If  then 
    Exit Function
  end if
end function

If I replace the exit function with return false or if I insert a SomeFunction = false then the compiler error won't show up.

So yes, as stated before, Visual Basic should default the return value to the default value of the return type, but it somehow crashed the compilation.

I suspect this behaviour is hard to reproduce. My bottom line is: Set return values explicitly. It's clearer to the code and might save you seven hours of debugging.