[fortran,patch] Extend symbol.c's check_conflict (PR29657)

[Paul Thomas]

Tobias Burnus wrote:
> :ADDPATCH fortran:
>
> This patch adds the following conflicts:
>
> * FUNCTION name conflicts with SAVE
>   
5.2.4 SAVE
Constraint: An object-name shall not be the name of an object in a 
common block, a dummy
argument name, a procedure name, a function result name, an automatic 
data object
name, or the name of an object with the PARAMETER attribute.

As far as I can see, all the others are there.

> * SUBROUTINE name conflicts with DIMENSION
> * PROGRAM and MODULE names conflicts with DIMENSION
> Those should be obvious. I couldn't find a good reference, though.
>   
Neither could I; as you say, they are obvious.
>
> * DUMMY ARGUMENTS conflict with ENTRY
> This is explicitly forbidden in Fortran 2003
> C1255
>   
12.5.2.5 ENTRY statement
Constraint: Within the subprogram containing the entry-stmt, the 
entry-name shall not appear as a
dummy argument in the FUNCTION or SUBROUTINE statement or in another
ENTRY statement and it shall not appear in an EXTERNAL or INTRINSIC 
statement.

> * DUMMY ARGUMENTS conflict with INTRINSIC
> It it not stated as allowed - contrary to EXTERNAL where it is
> explicitly allowed (see 12.3.2.2)
>   
12.3.2.3 INTRINSIC statement
....snip....
NOTE 12.11
A name shall not appear in both an EXTERNAL and an INTRINSIC statement 
in the same
scoping unit.

which implies the constraint that you are applying.

OK  for trunk.

Thanks

Paul