Y2038: Add 64-bit time for all architectures

glibc support for 64-bit time_t on 32-bit architectures
will involve:

- Using 64-bit times inside glibc, with conversions
  to and from 32-bit times taking place as necessary
  for interfaces using such times.

- Adding 64-bit-time support in the glibc public API.
  This support should be dynamic, i.e. glibc should
  provide both 32-bit and 64-bit implementations and
   let user code choose at compile time whether to use
   the 32-bit or 64-bit interfaces.

This requires a glibc-internal name for a type for times
that are always 64-bit.

Based on __TIMESIZE, a new macro is defined, __TIME64_T_TYPE,
 which is always the right __*_T_TYPE to hold a 64-bit-time.
__TIME64_T_TYPE equals __TIME_T_TYPE if __TIMESIZE equals 64
and equals __SQUAD_T_TYPE otherwise.

__time64_t can then replace uses of internal_time_t.

This patch was tested by running 'make check' on branch
master then applying this patch and its predecessor and
running 'make check' again, and checking that both 'make
check' yield identical results. This was done on
x86_64-linux-gnu and i686-linux-gnu.

	* bits/time64.h: New file.
	* include/time.h: Replace internal_time_t with __time64_t.
	* posix/bits/types (__time64_t): Add.
	* stdlib/Makefile: Add bits/time64.h to includes.
	* time/tzfile.c: Replace internal_time_t with __time64_t.

1 files changed, 1 insertions, 5 deletions

diff --git a/include/time.h b/include/time.h
index e30c5fc3b1..861b1acfb7 100644
--- a/include/time.h
+++ b/include/time.h
@@ -26,10 +26,6 @@ extern __typeof (clock_getcpuclockid) __clock_getcpuclockid;
 /* Now define the internal interfaces.  */
 struct tm;
 
-/* time_t variant for representing time zone data, independent of
-   time_t.  */
-typedef __int64_t internal_time_t;
-
 /* Defined in mktime.c.  */
 extern const unsigned short int __mon_yday[2][13] attribute_hidden;
 
@@ -43,7 +39,7 @@ extern int __use_tzfile attribute_hidden;
 
 extern void __tzfile_read (const char *file, size_t extra,
 			   char **extrap) attribute_hidden;
-extern void __tzfile_compute (internal_time_t timer, int use_localtime,
+extern void __tzfile_compute (__time64_t timer, int use_localtime,
 			      long int *leap_correct, int *leap_hit,
 			      struct tm *tp) attribute_hidden;
 extern void __tzfile_default (const char *std, const char *dst,