The IEEE standard for floating point operations, IEEE 754, was
standardized in 1985. The ANSI standard for Common Lisp specifies
that implementations purporting to conform to this IEEE standard
should have the `:ieee-floating-point` keyword on the
`*features*` variable. However, there is no discussion of
what purporting to conform to the IEEE 754 standard means in the
context of Common Lisp.

In the short term, we aim to provide a comformance test for
reasonable expectations of a Common Lisp implementation purporting
to conform to the IEEE 754 standard. While we hope that this
conformance test will also be useful to implementors not claiming
conformance with `:ieee-floating-point`, they are not our
primary audience.

Development milestones for thise goals might include

- adaption of the UCBTEST tests for the IEEE-specified operations (addition, subtraction, multiplication, division, square root and rounding);
- evaluation and adaption of the ucblibtests from UCBTEST for transcendental functions with real-valued answers;
- further development of ucblibtests to enable testing of complex-valued function calls;
- development of an IEEE floating point unit simulator, in single-float, double-float and extended modes, and random tests of implementations against this reference implementation;
- development of an arbitrary-precision transcendental function evaluator (with knowledge of branch cuts specified in ANSI Common Lisp) and random tests of implementations against this.

- Evaluation of the ongoing revision of the standard, IEEE 754R, and adjustment or development of tests as appropriate;
- Cross-implementation development of functionality needed for control over floating point evaluation, such as trap masking, rounding mode control;
- Standardization of the meaning of
`:ieee-floating-point`for Common Lisp implementations.

- This website. Send suggestions and corrections to the development mailing list.
- Mailing lists: announce, cvs, devel.
- CVS

- The IEEE 754 standard
- Much ado about zero's sign
- What every computer scientst should know about floating point arithmetic
- comp.arch.arithmetic
- Lots of other stuff by Kahan
- Mailing lists of the 754r team

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