diff options
| -rw-r--r-- | mcon/U/d_difftime.U | 50 |
1 files changed, 43 insertions, 7 deletions
diff --git a/mcon/U/d_difftime.U b/mcon/U/d_difftime.U index 06aa376..c558753 100644 --- a/mcon/U/d_difftime.U +++ b/mcon/U/d_difftime.U @@ -1,6 +1,6 @@ ?RCS: $Id$ ?RCS: -?RCS: Copyright (c) 1991-1997, 2004-2006, Raphael Manfredi +?RCS: Copyright (c) 1991-1997, 2004-2006, 2013 Raphael Manfredi ?RCS: ?RCS: You may redistribute only under the terms of the Artistic Licence, ?RCS: as specified in the README file that comes with the distribution. @@ -10,23 +10,30 @@ ?RCS: ?RCS: Original Author: Andy Dougherty <doughera@lafcol.lafayette.edu> ?RCS: -?RCS: $Log: d_difftime.U,v $ -?RCS: Revision 3.0.1.1 1994/08/29 16:07:31 ram -?RCS: patch32: created by ADO -?RCS: -?MAKE:d_difftime: Trylink cat +?MAKE:d_difftime use_difftime: Assert Trylink cat ?MAKE: -pick add $@ %< ?S:d_difftime: ?S: This variable conditionally defines the HAS_DIFFTIME symbol, which ?S: indicates to the C program that the difftime() routine is available. ?S:. +?S:use_difftime: +?S: This variable conditionally defines the USE_DIFFTIME symbol, which +?S: indicates to the C program that the difftime() routine should be +?S: used to compare times. +?S:. ?C:HAS_DIFFTIME : ?C: This symbol, if defined, indicates that the difftime routine is ?C: available. ?C:. +?C:USE_DIFFTIME : +?C: This symbol, if defined, indicates that the difftime routine should +?C: really be used to compare times. +?C:. ?H:#$d_difftime HAS_DIFFTIME /**/ +?H:#$use_difftime USE_DIFFTIME /**/ ?H:. -?LINT:set d_difftime +?LINT:set d_difftime use_difftime +?T:avoid_difftime : see if difftime exists $cat >try.c <<EOC #include <time.h> @@ -42,3 +49,32 @@ cyn=difftime set d_difftime eval $trylink +@if USE_DIFFTIME || use_difftime +: see whether difftime should be used +case "$d_difftime" in +"$define") + $cat >try.c <<EOC +#include "static_assert.h" +#include <time.h> +int main(void) +{ +?X: If time_t is not a signed integer type, we cannot calculate properly +?X: with the raw values. Define USE_DIFFTIME when this does not compile. + STATIC_ASSERT((time_t) -1 < 0); + return 0; +} +EOC + cyn="whether difftime() can be avoided" + set avoid_difftime + eval $trylink + ;; +*) avoid_difftime="$define";; +esac +case "$avoid_difftime" in +"$define") val="$undef";; +*) val="$define";; +esac +set use_difftime +eval $setvar + +@end |