Similar to the D/C prefixes to real functions to specify the input/output types, GNU Fortran offers B/I/J/K prefixes to integer functions for compatibility with DEC programs. The types implied by each are:
B-INTEGER(kind=1)I-INTEGER(kind=2)J-INTEGER(kind=4)K-INTEGER(kind=8)
GNU Fortran supports these with the flag -fdec-intrinsic-ints. Intrinsics for which prefixed versions are available and in what form are noted in Intrinsic Procedures. The complete list of supported intrinsics is here:
| Intrinsic | B | I | J | K | 
|---|---|---|---|---|
|  | BABS | IIABS | JIABS | KIABS | 
|  | BBTEST | BITEST | BJTEST | BKTEST | 
|  | BIAND | IIAND | JIAND | KIAND | 
|  | BBCLR | IIBCLR | JIBCLR | KIBCLR | 
|  | BBITS | IIBITS | JIBITS | KIBITS | 
|  | BBSET | IIBSET | JIBSET | KIBSET | 
|  | BIEOR | IIEOR | JIEOR | KIEOR | 
|  | BIOR | IIOR | JIOR | KIOR | 
|  | BSHFT | IISHFT | JISHFT | KISHFT | 
|  | BSHFTC | IISHFTC | JISHFTC | KISHFTC | 
|  | BMOD | IMOD | JMOD | KMOD | 
|  | BNOT | INOT | JNOT | KNOT | 
|  | -- | FLOATI | FLOATJ | FLOATK |