5.1 KIND Type Parameters

The KIND type parameters supported by GNU Fortran for the primitive data types are:

INTEGER

1, 2, 4, 8*, 16*, default: 4 (1)

LOGICAL

1, 2, 4, 8*, 16*, default: 4 (1)

REAL

4, 8, 10**, 16**, default: 4 (2)

COMPLEX

4, 8, 10**, 16**, default: 4 (2)

CHARACTER

1, 4, default: 1

* = not available on all systems
** = not available on all systems; additionally 10 and 16 are never available at the same time
(1) Unless -fdefault-integer-8 is used
(2) Unless -fdefault-real-8 is used

The KIND value matches the storage size in bytes, except for COMPLEX where the storage size is twice as much (or both real and imaginary part are a real value of the given size). It is recommended to use the SELECT_*_KIND intrinsics instead of the concrete values.