On 12/7/05, Bradley Lucier <lucier@math.purdue.edu> wrote:
Gambit 4.0b15 fails some srfi-56 tests because the first instance of 2.0 is not 2; unfortunately, Gambit-C calculates
(expt 2.0 -1074)
as
(/ (expt 2.0 1074))
Hi, thanks for looking into this and getting it working with Gambit. The (expt 2.0 ...) form was there for the sake of Bigloo, for which (expt N -M) => 0 for all exact integers N, M > 1. This is clearly a bug on Bigloo's part, but it seemed safe to compensate for it. In particular, every other tested implementation correctly evaluates (expt 2.0 -1024). [Or so I thought. Scheme48 also gives 0.0 for this.] Choosing between the lesser of two evil^H^H^H^Hbugs, I'd consider Bigloo's behavior the more egregious here, so let's call (expt 2 ...) the correct reference form. Congratulations, Gambit now passes all tests! [And possibly the latest version of Scheme48 does as well.] -- Alex