Joseph Myers 7d7724e795 Fix year 2039 bug for localtime with 64-bit time_t (bug 22639). ... Bug 22639 reports localtime failing to handle time offset transitions correctly in 2039 and later on platforms with 64-bit time_t. The problem is the use of SECSPERDAY (constant 86400) in calculations such as t = ((year - 1970) * 365 + /* Compute the number of leapdays between 1970 and YEAR (exclusive). There is a leapday every 4th year ... */ + ((year - 1) / 4 - 1970 / 4) /* ... except every 100th year ... */ - ((year - 1) / 100 - 1970 / 100) /* ... but still every 400th year. */ + ((year - 1) / 400 - 1970 / 400)) * SECSPERDAY; where t is of type time_t and year is of type int. Before my commit 92bd70fb85 (an update from tzcode, included in 2.26 and later releases), SECSPERDAY was obtained from a file imported from tzcode, where the value included a cast to int_fast32_t. On 64-bit platforms, glibc defines int_fast32_t to be long int, so 64-bit, but my patch resulted in it changing to int. (The bug would probably have existed even before my patch for x32, which has 64-bit time_t but 32-bit int_fast32_t, but I haven't verified that.) This patch fixes the problem by including a cast to time_t in the definition of SECSPERDAY. (64-bit time support for 32-bit systems should move such code that isn't a public interface to using the internal 64-bit version of time_t throughout.) Tested for x86_64 and x86. [BZ #22639] * time/tzset.c (SECSPERDAY): Cast to time_t. * time/tst-y2039.c: New file. * time/Makefile (tests): Add tst-y2039.		2021-08-27 17:26:03 -07:00
..
bits/types
sys
adjtime.c
alt_digit.c
asctime.c
bug-asctime_r.c
bug-asctime.c
bug-getdate1.c
bug-mktime1.c
clock.c
clocktest.c
ctime_r.c
ctime.c
datemsk
Depend
difftime.c
dysize.c
era.c
ftime.c
getdate.c
getitimer.c
gettimeofday.c
gmtime.c
lc-time-cleanup.c
localtime.c
Makefile	Fix year 2039 bug for localtime with 64-bit time_t (bug 22639).	2021-08-27 17:26:03 -07:00
mktime.c
offtime.c
setitimer.c
settimeofday.c
stime.c
strftime_l.c	Abbreviated alternative month names (%Ob) also added (bug 10871).	2018-01-22 11:26:55 +01:00
strftime.c
strptime_l.c	Abbreviated alternative month names (%Ob) also added (bug 10871).	2018-01-22 11:26:55 +01:00
strptime.c
test_time.c
time.c
time.h	time: Reference CLOCKS_PER_SEC in clock comment [BZ #22735]	2018-02-02 11:59:31 +01:00
timegm.c
timespec_get.c
tst_wcsftime.c
tst-ftime_l.c
tst-ftime.c
tst-getdate.c
tst-mktime2.c
tst-mktime3.c
tst-mktime.c
tst-posixtz.c
tst-strftime.c
tst-strptime2.c
tst-strptime3.c
tst-strptime-whitespace.c
tst-strptime.c	ru_RU, ru_UA: Add alternative month names (bug 10871).	2018-01-29 13:14:45 +01:00
tst-tzname.c
tst-y2039.c	Fix year 2039 bug for localtime with 64-bit time_t (bug 22639).	2021-08-27 17:26:03 -07:00
tzfile.c
tzset.c	Fix year 2039 bug for localtime with 64-bit time_t (bug 22639).	2021-08-27 17:26:03 -07:00
Versions
wcsftime_l.c
wcsftime.c