In intel compiler 2015, if I want to use the enum. I have to use it as follows
enumerator :: BLUE
So, the BLUE was set integer 4 as in the C lang.
Can I change it to integer 8?
There is no language in the Fortran standard to allow you to do that, nor do we automatically widen them with the /integer-size:64 switch.
As you probably saw, part of the definition of the Fortran ENUM is this:
For an enumeration, the kind is selected such that an integer type with that kind is interoperable (15.3.2) with the
corresponding C enumeration type.
If you need integer parameters that are bigger (or smaller) than 4-byte integers, then you will need to explicitly define each one.