The generated mock methods use some hardcoded variable/receiver names that can have conflicts with the argument names that are defined by the code for which the mock is generated when using the source generation method. Example: ```go type Example interface { Method(_m, _mr, m, mr int) } ``` ```go // Method mocks base method func (_m *MockExample) Method(_m int, _mr int, m int, mr int) { _m.ctrl.Call(_m, "Method", _m, _mr, m, mr) } ``` In the above example one of the interface method parameters is called `_m` but unfortunately the generated receiver name is also called `_m` so the mock code won't compile. The generator has to make sure that generated identifiers (e.g.: the receiver names) are always different from the arg names that might come from external sources.