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Hi Adhemerval, > On 18/01/2020 04:20, Lukasz Majewski wrote: > > Now, internally the deprecated stime uses __clock_settime64. This > > patch is necessary for having architectures with __WORDSIZE == 32 && > > __TIMESIZE == 32 (like e.g. ARM32) Y2038 safe. > > > > Build tests: > > ./src/scripts/build-many-glibcs.py glibcs > > --- > > time/stime.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/time/stime.c b/time/stime.c > > index 576fa9c0c9..963902126b 100644 > > --- a/time/stime.c > > +++ b/time/stime.c > > @@ -27,11 +27,11 @@ int > > attribute_compat_text_section > > __stime (const time_t *when) > > { > > - struct timespec ts; > > + struct __timespec64 ts; > > ts.tv_sec = *when; > > ts.tv_nsec = 0; > > > > - return __clock_settime (CLOCK_REALTIME, &ts); > > + return __clock_settime64 (CLOCK_REALTIME, &ts); > > } > > > > compat_symbol (libc, __stime, stime, GLIBC_2_0); > > > > For !__ASSUME_TIME64_SYSCALLS builds time_t will continue to be 32 > bits and stime will continue to be non Y2038 safe. This patch is a preparatory work for introducing support of -D_TIME_BITS=64 compilation flag when compiling programs with glibc [1]. Then the __USE_TIME_BITS64 is defined for exported glibc headers. After this the time_t will become __time64_t on e.g. ARM32 bits (__WORDSIZE==32 && __TIMESIZE==32). As pointed out by Joseph [3], without such code we will not be able atomically introduce _TIME_BITS=64 support. > Also, internally > __clock_settime will first try to issue __NR_clock_settime64, so > current code already accomplishes what this patch is aiming to do. There is a use case when we do need to call __clock_settime64 though: - ARM32 program is compiled with -D_TIME_BITS=64 - The clock_settime (or stime) internally uses __clock_settime() which in this case supports only 32 bit time API. To have this system Y2038 safe - one needs to call __clock_settime64 explicitly to support passing arguments via struct __timespec64. This is true for all calls of __clock_settime/__clock_gettime (functions to be used internally by glibc, as we ought to switch to e.g. struct __timespec64). Links: [1] - https://github.com/lmajewski/y2038_glibc/commit/e03c7188c72dd78d7141cf88f24dd2a5fd14c4f1#diff-a5ab6c74681eaf0569ed54f6bf0d7978R386 [2] - https://github.com/lmajewski/y2038_glibc/commit/e03c7188c72dd78d7141cf88f24dd2a5fd14c4f1#diff-c051022b496f12bd9028edb46b8ec04dR7 [3] - https://sourceware.org/ml/libc-alpha/2020-01/msg00369.html [4] - https://github.com/lmajewski/y2038_glibc/blob/glibc_settimeofday_64bit_conversion_v1/sysdeps/unix/sysv/linux/clock_settime.c#L57 Best regards, Lukasz Majewski -- DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-59 Fax: (+49)-8142-66989-80 Email: lukma@denx.de
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