2012/2/16 Guido van Rossum <gu...@python.org>: > On Thu, Feb 16, 2012 at 2:04 PM, Victor Stinner > <victor.stin...@gmail.com> wrote: >> It doesn't change anything to the Makefile issue, if timestamps are >> different in a single nanosecond, they are seen as different by make >> (by another program comparing the timestamp of two files using >> nanosecond precision). > > But make doesn't compare timestamps for equality -- it compares for > newer. That shouldn't be so critical, since if there is an *actual* > causal link between file A and B, the difference in timestamps should > always be much larger than 100 ns.
The problem is that shutil.copy2() produces sometimes *older* timestamp :-/ As shown in my previous email: in such case, make will always rebuild the second file instead of only build it once. Example with two consecutive runs: $ ./python diff.py 1329432426.650957952 1329432426.650958061 1.09E-7 $ ./python diff.py 1329432427.854957910 1329432427.854957819 -9.1E-8 Victor _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com