@section @code{ISO_C_BINDING}
@table @asis
@item @emph{Standard}:
-Fortran 2003 and later
+Fortran 2003 and later, GNU extensions
@end table
The following intrinsic procedures are provided by the module; their
The @code{C_INT_FAST...} parameters have therefore the value @math{-2}
and cannot be used as KIND type parameter of the @code{INTEGER} type.
-@multitable @columnfractions .15 .35 .35
-@item Fortran Type @tab Named constant @tab C type
+In addition to the integer named constants required by the Fortran 2003
+standard, GNU Fortran provides as an extension named constants for the
+128-bit integer types supported by the C compiler: @code{C_INT128_T,
+C_INT_LEAST128_T, C_INT_FAST128_T}.
+
+@multitable @columnfractions .15 .35 .35 .35
+@item Fortran Type @tab Named constant @tab C type @tab Extension
@item @code{INTEGER}@tab @code{C_INT} @tab @code{int}
@item @code{INTEGER}@tab @code{C_SHORT} @tab @code{short int}
@item @code{INTEGER}@tab @code{C_LONG} @tab @code{long int}
@item @code{INTEGER}@tab @code{C_INT16_T} @tab @code{int16_t}
@item @code{INTEGER}@tab @code{C_INT32_T} @tab @code{int32_t}
@item @code{INTEGER}@tab @code{C_INT64_T} @tab @code{int64_t}
+@item @code{INTEGER}@tab @code{C_INT128_T} @tab @code{int128_t} @tab Ext.
@item @code{INTEGER}@tab @code{C_INT_LEAST8_T} @tab @code{int_least8_t}
@item @code{INTEGER}@tab @code{C_INT_LEAST16_T} @tab @code{int_least16_t}
@item @code{INTEGER}@tab @code{C_INT_LEAST32_T} @tab @code{int_least32_t}
@item @code{INTEGER}@tab @code{C_INT_LEAST64_T} @tab @code{int_least64_t}
+@item @code{INTEGER}@tab @code{C_INT_LEAST128_T} @tab @code{int_least128_t} @tab Ext.
@item @code{INTEGER}@tab @code{C_INT_FAST8_T}* @tab @code{int_fast8_t}
@item @code{INTEGER}@tab @code{C_INT_FAST16_T}* @tab @code{int_fast16_t}
@item @code{INTEGER}@tab @code{C_INT_FAST32_T}* @tab @code{int_fast32_t}
@item @code{INTEGER}@tab @code{C_INT_FAST64_T}* @tab @code{int_fast64_t}
+@item @code{INTEGER}@tab @code{C_INT_FAST128_T}* @tab @code{int_fast128_t} @tab Ext.
@item @code{INTEGER}@tab @code{C_INTMAX_T} @tab @code{intmax_t}
@item @code{INTEGER}@tab @code{C_INTPTR_T} @tab @code{intptr_t}
@item @code{REAL} @tab @code{C_FLOAT} @tab @code{float}