Could you provide a bit more source code?  I can't really see what's happening with only a variable declaration.  Is upcase an argument to a procedure, a function in your project, or just a local variable?

I have found that a program that compiled and run succesfully with SimplyFortran 2.13 (which uses gfortran 4.8.2), now, with SimplyFortran 2.14 (which uses gfortran 4.9.0), shows this compilation error:

      character*80 buffer,upcase
                                1
Error: Explicit interface required for 'upcase' at (1): result with non-constant
 character length

If I use the last version of gfortran (4.10), the same error appears. I reinstalled again SimplyFortran 2.13.

Do you know what is the cause of the error?

Thanks,

Marcelino