6.1.22 Type variants for integer intrinsics

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
ABS BABS IIABS JIABS KIABS
BTEST BBTEST BITEST BJTEST BKTEST
IAND BIAND IIAND JIAND KIAND
IBCLR BBCLR IIBCLR JIBCLR KIBCLR
IBITS BBITS IIBITS JIBITS KIBITS
IBSET BBSET IIBSET JIBSET KIBSET
IEOR BIEOR IIEOR JIEOR KIEOR
IOR BIOR IIOR JIOR KIOR
ISHFT BSHFT IISHFT JISHFT KISHFT
ISHFTC BSHFTC IISHFTC JISHFTC KISHFTC
MOD BMOD IMOD JMOD KMOD
NOT BNOT INOT JNOT KNOT
REAL -- FLOATI FLOATJ FLOATK

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