(long_time_expected_width): Revert last change, just to

be paranoid, and add a comment explaining why.
Paul Eggert mentioned the possibility.

1 files changed, 14 insertions, 9 deletions

diff --git a/src/ls.c b/src/ls.c
index 561d7fe52..a3d4bde71 100644
--- a/src/ls.c
+++ b/src/ls.c
@@ -3068,15 +3068,20 @@ long_time_expected_width (void)
       struct tm const *tm = localtime (&epoch);
       char buf[TIME_STAMP_LEN_MAXIMUM + 1];
 
-      /* The above use of localtime cannot fail.  */
-      assert (tm != NULL);
-
-      {
-	size_t len =
-	  nstrftime (buf, sizeof buf, long_time_format[0], tm, 0, 0);
-	if (len != 0)
-	  width = mbsnwidth (buf, len, 0);
-      }
+      /* In case you're wondering if localtime can fail with an input time_t
+	 value of 0, let's just say it's very unlikely, but not inconceivable.
+	 The TZ environment variable would have to specify a time zone that
+	 is 2**31-1900 years or more ahead of UTC.  This could happen only on
+	 a 64-bit system that blindly accepts e.g., TZ=UTC+20000000000000.
+	 However, this is not possible with Solaris 10 or glibc-2.3.5, since
+	 their implementations limit the offset to 167:59 and 24:00, resp.  */
+      if (tm)
+	{
+	  size_t len =
+	    nstrftime (buf, sizeof buf, long_time_format[0], tm, 0, 0);
+	  if (len != 0)
+	    width = mbsnwidth (buf, len, 0);
+	}
 
       if (width < 0)
 	width = 0;