[Patch, Fortran] PR34514 - prevent double initialization and dimension changes after initialization

[Tobias Burnus]

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http://gcc.gnu.org/ml/fortran/2007-12/msg00221.html

Tobias Burnus wrote:
> It is completely unclear what value "n" has after:
>
>   integer :: n = 4
>   dimension :: n(3)
>
>
> similarly invalid is:
>   integer :: n = 5
>   parameter (n = 7)
>
> This patch adds checks to reject this.
>   
[...]
> Build and regtested on x86-64. OK for the trunk?
>