From 0514ad126b853b3742dd4cca531b33779bbc5289 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Sat, 18 Nov 2000 05:41:45 +0000 Subject: [PATCH] Tweak AbsoluteTimeIsReal() to avoid compiler bugs on machines where a > comparison against INT_MIN may do the wrong thing. Per suggestion from Andreas. --- src/include/utils/nabstime.h | 35 ++++++++++++----------------------- 1 file changed, 12 insertions(+), 23 deletions(-) diff --git a/src/include/utils/nabstime.h b/src/include/utils/nabstime.h index 683b81e2e4..f6719dbeb9 100644 --- a/src/include/utils/nabstime.h +++ b/src/include/utils/nabstime.h @@ -7,13 +7,14 @@ * Portions Copyright (c) 1996-2000, PostgreSQL, Inc * Portions Copyright (c) 1994, Regents of the University of California * - * $Id: nabstime.h,v 1.26 2000/06/09 01:11:15 tgl Exp $ + * $Id: nabstime.h,v 1.27 2000/11/18 05:41:45 tgl Exp $ * *------------------------------------------------------------------------- */ #ifndef NABSTIME_H #define NABSTIME_H +#include #include #include "fmgr.h" @@ -78,37 +79,25 @@ typedef TimeIntervalData *TimeInterval; #define CURRENT_ABSTIME ((AbsoluteTime) 0x7FFFFFFD) /* 2147483646 (2^31 - 2) */ #define NOEND_ABSTIME ((AbsoluteTime) 0x7FFFFFFC) /* 2147483645 (2^31 - 3) */ #define BIG_ABSTIME ((AbsoluteTime) 0x7FFFFFFB) /* 2147483644 (2^31 - 4) */ - -#if defined(_AIX) -/* - * AIX considers 2147483648 == -2147483648 (since they have the same bit - * representation) but uses a different sign sense in a comparison to - * these integer constants depending on whether the constant is signed - * or not! - */ -#define NOSTART_ABSTIME ((AbsoluteTime) INT_MIN) -#else -#define NOSTART_ABSTIME ((AbsoluteTime) 0x80000001) /* -2147483647 (- 2^31) */ -#endif /* _AIX */ +#define NOSTART_ABSTIME ((AbsoluteTime) INT_MIN) /* -2147483648 */ #define INVALID_RELTIME ((RelativeTime) 0x7FFFFFFE) /* 2147483647 (2^31 - 1) */ #define AbsoluteTimeIsValid(time) \ ((bool) ((time) != INVALID_ABSTIME)) +/* + * Because NOSTART_ABSTIME is defined as INT_MIN, there can't be any + * AbsoluteTime values less than it. Therefore, we can code the test + * "time > NOSTART_ABSTIME" as "time != NOSTART_ABSTIME", which avoids + * compiler bugs on some platforms. --- tgl & az, 11/2000 + */ #define AbsoluteTimeIsReal(time) \ - ((bool) (((AbsoluteTime) time) < NOEND_ABSTIME && \ - ((AbsoluteTime) time) > NOSTART_ABSTIME)) + ((bool) (((AbsoluteTime) (time)) < NOEND_ABSTIME && \ + ((AbsoluteTime) (time)) != NOSTART_ABSTIME)) #define RelativeTimeIsValid(time) \ - ((bool) (((RelativeTime) time) != INVALID_RELTIME)) - -/* - * getSystemTime - * Returns system time. - */ -#define getSystemTime() \ - ((time_t) (time(0l))) + ((bool) (((RelativeTime) (time)) != INVALID_RELTIME)) /*