Setting Integer and Floating-point Data Types

See the summary of these options.

Integer Data

The -i2, -i4, and -i8 options specify that all quantities of INTEGER type and unspecified KIND occupy two, four or eight bytes, respectively. All quantities of LOGICAL type and unspecified KIND also occupy two, four or eight bytes, respectively.

All logical constants and all small integer constants occupy two, four or eight bytes, respectively.

The default is four bytes, -i4.

Floating-point Data

TThe -r{4|8|16} option defines the KIND for real variables in 4, 8, and 16 bytes. The default is -r4.

The -r8, -autodouble, and -r16 options specify floating-point data.

The -r8 option directs the compiler to treat all variables, constants, functions and intrinsics as DOUBLE PRECISION, and all complex quantities as DOUBLE COMPLEX. The -autodouble option has the same effect as the -r8 option.

The -r16 option directs the compiler to treat all variables, constants, functions and intrinsics as DOUBLE PRECISION, and all complex quantities as DOUBLE COMPLEX. This option changes the default size of real numbers to 16 bytes.