diff options
Diffstat (limited to 'm4/mktime.m4')
| -rw-r--r-- | m4/mktime.m4 | 21 |
1 files changed, 12 insertions, 9 deletions
diff --git a/m4/mktime.m4 b/m4/mktime.m4 index f2b131ba456..56b2416d619 100644 --- a/m4/mktime.m4 +++ b/m4/mktime.m4 @@ -1,4 +1,4 @@ -# serial 17 +# serial 19 dnl Copyright (C) 2002-2003, 2005-2007, 2009-2011 Free Software Foundation, dnl Inc. dnl This file is free software; the Free Software Foundation @@ -165,20 +165,23 @@ main () int result = 0; time_t t, delta; int i, j; + int time_t_signed_magnitude = (time_t) ~ (time_t) 0 < (time_t) -1; + int time_t_signed = ! ((time_t) 0 < (time_t) -1); /* This test makes some buggy mktime implementations loop. Give up after 60 seconds; a mktime slower than that isn't worth using anyway. */ alarm (60); - for (;;) - { - t = (time_t_max << 1) + 1; - if (t <= time_t_max) - break; - time_t_max = t; - } - time_t_min = - ((time_t) ~ (time_t) 0 == (time_t) -1) - time_t_max; + time_t_max = (! time_t_signed + ? (time_t) -1 + : ((((time_t) 1 << (sizeof (time_t) * CHAR_BIT - 2)) - 1) + * 2 + 1)); + time_t_min = (! time_t_signed + ? (time_t) 0 + : time_t_signed_magnitude + ? ~ (time_t) 0 + : ~ time_t_max); delta = time_t_max / 997; /* a suitable prime number */ for (i = 0; i < N_STRINGS; i++) |