diff options
| author | Paul Eggert | 2019-08-16 16:25:02 -0700 |
|---|---|---|
| committer | Paul Eggert | 2019-08-16 16:27:27 -0700 |
| commit | f9fd12a30b3d94eb48f7b309907d136d7b2682ac (patch) | |
| tree | d00aa93beec6eb1013127ee251342f39f135a994 /src/bytecode.c | |
| parent | e82923c817159c751aa9c902093a46b9457e8499 (diff) | |
| download | emacs-f9fd12a30b3d94eb48f7b309907d136d7b2682ac.tar.gz emacs-f9fd12a30b3d94eb48f7b309907d136d7b2682ac.zip | |
Fix time-add rounding bug
Without this fix, time arithmetic yielded results that were not
mathematically accurate, even though the exact results were
representable; for example, (time-add 0 1e-13) yielded a timestamp
equal to 0 instead of to 1e-13.
* lisp/timezone.el (timezone-time-from-absolute):
Let time-add do its thing rather than using floating point
internally, which has rounding errors. We now have bignums and so
don’t need floating point to avoid overflow issues.
* src/timefns.c (timeform_sub_ps_p): New function.
(time_arith): If either argument is a float, represent the
result exactly instead of discarding sub-ps info.
* test/lisp/timezone-tests.el (timezone-tests-time-from-absolute):
Don’t assume (HI LO US PS) timestamp format.
* test/src/emacs-module-tests.el (mod-test-add-nanosecond/valid):
Don’t assume that time-add discards sub-ns info.
* test/src/timefns-tests.el (time-rounding-tests):
Add regression test to detect time-add rounding bug.
Diffstat (limited to 'src/bytecode.c')
0 files changed, 0 insertions, 0 deletions