[PATCH v2 3/4] system_data_types.7: correct struct timespec::tv_nsec type for x32

[наб <nabijaczleweli@xxxxxxxxxxxxxxxxxx>]

There are three files that govern userspace struct timespec on glibc:
1. bits/wordsize.h, defining:
   (a) __WORDSIZE to 32 on ILP32 and 64 on LP64
   (b) on x32: __SYSCALL_WORDSIZE to 64
2. bits/timesize.h, defining
   (a) __TIMESIZE to __WORDSIZE, except on x32 where it's 64
3. bits/types/struct_timespec.h, declaring struct timespec as:
     struct timespec
     {
      __time_t tv_sec;      /* Seconds.  */
     #if __WORDSIZE == 64 \
      || (defined __SYSCALL_WORDSIZE && __SYSCALL_WORDSIZE == 64) \
      || __TIMESIZE == 32
      __syscall_slong_t tv_nsec;    /* Nanoseconds.  */
     #else
     # if __BYTE_ORDER == __BIG_ENDIAN
      int: 32;           /* Padding.  */
      long int tv_nsec;  /* Nanoseconds.  */
     # else
      long int tv_nsec;  /* Nanoseconds.  */
      int: 32;           /* Padding.  */
     # endif
     #endif
     };
   this has two side-effects: struct timespec
   (a) is always sizeof==time_t+8, and
   (b) has tv_nsec as __syscall_slong_t
       *and* !is_same<__syscall_slong_t, long>
       if using LP64 syscalls on an ILP32 system, i.e. on x32.

This means, that the simplified
  struct timespec {
      time_t  tv_sec;  /* Seconds */
      long    tv_nsec; /* Nanoseconds [0 .. 999999999] */
  };
declaration is *invalid* for x32,
where struct timespec::tv_nsec is an int64_t (long long).

Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@xxxxxxxxxxxxxxxxxx>
---
 man7/system_data_types.7 | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/man7/system_data_types.7 b/man7/system_data_types.7
index 1e6a3f74c..80679b180 100644
--- a/man7/system_data_types.7
+++ b/man7/system_data_types.7
@@ -1544,7 +1544,11 @@ or
 .EX
 struct timespec {
     time_t  tv_sec;  /* Seconds */
+#if !(__x86_64__ && __ILP32__ /* == x32 */)
     long    tv_nsec; /* Nanoseconds [0 .. 999999999] */
+#else
+    long long tv_nsec;
+#endif
 };
 .EE
 .PP
-- 
2.30.2

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