CMUCL supports three floating point formats:
single-float, double-float and
double-double-float. The first two are implemented with
IEEE single and double float arithmetic, respectively. The last is an
extension; see extended-float for more information.
short-float is a synonym for single-float, and
long-float is a synonym for double-float. The initial
value of read-default-float-format is single-float.
Both single-float and double-float are represented with
a pointer descriptor, so float operations can cause number consing.
Number consing is greatly reduced if programs are written to allow the
use of non-descriptor representations (see numeric-types.)