Internal representation of LOGICAL variables (The GNU Fortran Compiler) (original) (raw)

4.2 Internal representation of LOGICAL variables ¶

The Fortran standard does not specify how variables of LOGICALtype are represented, beyond requiring that LOGICAL variables of default kind have the same storage size as default INTEGERand REAL variables. The GNU Fortran internal representation is as follows.

A LOGICAL(KIND=N) variable is represented as anINTEGER(KIND=N) variable, however, with only two permissible values: 1 for .TRUE. and 0 for.FALSE.. Any other integer value results in undefined behavior.

See also Argument passing conventions and Interoperability with C.