Variable as a reference or value to a function

[Kernelpanic]

When I pass something by value to a function or Sub(procedure), I work with a copy of the variable because I don't want it to change itself.
It doesn't seem to work with a function because the original variable is changed. The result is correct:
eingabe = 5
eingabe = eingabe + 3 -> 8
AlsWert = eingabe + 3 -> 11