bug#5950: defvaralias after defvar should be warned in runtime

[Clément Pit-Claudel]

On 2018-08-01 17:46, Stefan Monnier wrote:
>> Warning (defvaralias): Overwriting value of
>> ‘flycheck-python-pylint-executable’ by aliasing to
>> ‘python-shell-interpreter’
> 
> This warning tells you that the variable
> `flycheck-python-pylint-executable` already had a value before the call
> to `defvaralias`, and that this value is lost at this point.
> 
> Usually the warning is due to the defvaralias call being performed after
> the corresponding `defvar`s.

Right. But why is that a problem?