On 2013-05-14 15:39, Corinna Vinschen wrote: > On May 13 18:57, Corinna Vinschen wrote: >> On May 13 18:41, Denis Excoffier wrote: >>> On 2013-05-13 17:49, Corinna Vinschen wrote: >>>> Erm... hang on. Is that really a problem? 2147483647 is 0x7fffffff, >>>> which is the maximum you get with a 4 byte time_t (== signed long) >>>> anyway. If you switch the date to 2038-01-20, the value will be >>>> negative, and therefore outside the scope of the 4 byte time_t. So this >>>> is a hard restriction of using 4 byte time_t. >>>> >>>> The solution is: >>>> >>>> - Either somebody changes 32 bit Cygwin to 8 byte time_t while keeping >>>> all the 4 byte time_t APIs intact to maintain compatibility with >>>> existing binaries(*), >>>> >>>> - or, you switch to a 64 bit Windows and use 64 bit Cygwin ;) >>>> >>> I understand. >>> >>> I suppose you will however be willing to provide us a means to workaround >>> the "autoconf mktime usability test failing" (see for example in >>> gawk-4.1.0 where all the tm fields are set to 128). Now, instead of only >>> failing (i presume), it hangs. Sorry, this specific point should have been >>> noticed in my original post. >>> >>> Or do we have to patch every impacted ./configure? >> >> Good point. I guess the right thing to do here is for mktime to >> return -1 instead of hanging. I look into that. > > Looks like this is a result of gcc optimization settings. The upstream > code computing time_t <-> struct tm conversions requires integer > overflow to be fully defined, but gcc's -O2 option sets > -fstrict-overflow which results in all kinds of agressive integer > optimizations which disabled utilizing integer overflows for serious > purposes. I fixed that by setting the -fwrapv option when building the > affected localtime.cc file (thanks to Kai Tietz for pointing this out). > I can confirm that the last snapshot (20130516) fixes the problem.
Thank you. Denis Excoffier. -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
