“This is not a valid initialization expression” while using NULL() to initialize pointer

Hello everybody,

In the module i'm writing, I'm using a module called FluidProp that uses DWINTY. I have seen on a help page that there are conflicts with the null statement, and that it could be resolved by writing 'USE DFWINTY, NULL0=>NULL' so that NULL and NULL0 can be used throughout the program. 

I am still getting the aforementioned error (This is not a valid initialization expression) when I write the suggested correction.

Here is what I'm typing to get the error:

TYPE :: steam_perfor_type
    CHARACTER(8):: name
    DOUBLE PRECISION    ::  TC, HRSG, BC, CC, Pdiff, error, Q, P_TC, P_CC
END TYPE steam_perfor_type
TYPE(steam_perfor_type),TARGET :: steam_perform
TYPE(steam_perfor_type),POINTER :: perf=>NULL( )

Any help would be greatly appreciated.