"Terry Reedy" <[EMAIL PROTECTED]> writes: > "Tim Peters" <[EMAIL PROTECTED]> wrote in message > news:[EMAIL PROTECTED] > > [Donn Cave] > >> I ran into a phenomenon that seemed odd to me, while testing a > >> build of Python 2.4.1 on BeOS 5.04, on PowerPC 603e. > >> > >> test_builtin.py, for example, fails a couple of tests with errors > >> claiming that apparently identical floating point values aren't equal. > >> But it only does that when imported, and only when the .pyc file > >> already exists. Not if I execute it directly (python test_builtin.py), > >> or if I delete the .pyc file before importing it and running > >> test_main(). > > This is a known problem with marshalling INFs and/or NANs.
I hope you've also read all the bits and pieces where Tim says "whatever happens to INFs and NANs is a platform dependent crapshoot". We don't test platform dependent crapshoots in test_builtin (or at least, I hope not!). > *This* has supposedly been fixed for 2.5. Actually, it's likely that Donn's failure has been fixed for Python 2.5 as well, at least if Tim's guess is correct, because the C string->float routines aren't invovled in loading .pycs any more. > > It would be most helpful to open a bug report, with the output from > > failing tests. > > And assign to Tim. That's mean! :) > >In general, this can > > happen if the platform C string<->float routines are so poor that > > > > eval(repr(x)) != x > ... > > The ultimate cause is most likely in the platform C library's > > string<->float routines (sprintf, strtod, that kind of thing). > > It would also be helpful if you could do some tests in plain C (no Python) > testing, for instance, the same values that failed. Hardly anyone else can > ;-). If you confirm a problem with the C library, you can close the report > after opening, leaving it as a note for anyone else working with that > platform. I agree with this bit! Cheers, mwh -- 112. Computer Science is embarrassed by the computer. -- Alan Perlis, http://www.cs.yale.edu/homes/perlis-alan/quotes.html -- http://mail.python.org/mailman/listinfo/python-list
