Obsolescent Language Features in Fortran 95

Some language features, considered redundant in Fortran 90 are identified as obsolescent in Fortran 95.

Compaq Fortran flags these features if you specify the /stand compiler option.

Other methods are suggested to achieve the functionality of the following obsolescent features:

• Alternate returns

  To replace this functionality, it is recommended that you use an integer variable to return a value to the calling program, and let the calling program use a CASE construct to test the value and perform operations.

• Arithmetic IF

  To replace this functionality, it is recommended that you use an IF statement or construct.

• Assumed-length character functions

  To replace this functionality, it is recommended that you use one of the following:

  • An automatic character-length function, where the length of the function result is declared in a specification expression
  • A subroutine whose arguments correspond to the function result and the function arguments

  Dummy arguments of a function can still have assumed character length; this feature is not obsolescent.

• CHARACTER*(*) form of CHARACTER declaration

  To replace this functionality, it is recommended that you use the Fortran 90 forms of specifying a length selector in CHARACTER declarations (see Declaration Statements for Character Types).

• Computed GO TO statement

  To replace this functionality, it is recommended that you use a CASE construct.

• DATA statements among executable statements

  This functionality has been included since FORTRAN 66, but is considered to be a potential source of errors.

• Fixed source form

  Newer methods of entering data have made this source form obsolescent and error-prone.

  The recommended method for coding is to use free source form.

• Shared DO termination and termination on a statement other than END DO or CONTINUE

  To replace this functionality, it is recommended that you use an END DO statement (see Forms for DO Constructs) or a CONTINUE statement.

• Statement functions

  To replace this functionality, it is recommended that you use an internal function.