From 3be772cadc2919733d05ee7b41da4d97d013ba05 Mon Sep 17 00:00:00 2001
From: Tom Lane
Date: Sun, 29 Nov 1998 01:59:00 +0000
Subject: Change exp() behavior to generate error on underflow rather than
 silently returning zero on some machines.  Correct float8 regress test to
 agree.  Also fix pow() overflow/underflow check to work correctly on HPUX.

---
 src/backend/utils/adt/float.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

(limited to 'src/backend/utils/adt/float.c')

diff --git a/src/backend/utils/adt/float.c b/src/backend/utils/adt/float.c
index b1de92f643e..5dfa2dfbadd 100644
--- a/src/backend/utils/adt/float.c
+++ b/src/backend/utils/adt/float.c
@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/float.c,v 1.33 1998/09/01 04:32:32 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/float.c,v 1.33.2.1 1998/11/29 01:58:59 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1041,7 +1041,7 @@ dpow(float64 arg1, float64 arg2)
 #endif
 	*result = (float64data) pow(tmp1, tmp2);
 #ifndef finite
-	if (errno == ERANGE)
+	if (errno != 0)			/* on some machines both EDOM & ERANGE can occur */
 #else
 	if (!finite(*result))
 #endif
@@ -1074,7 +1074,8 @@ dexp(float64 arg1)
 #ifndef finite
 	if (errno == ERANGE)
 #else
-	if (!finite(*result))
+	/* infinity implies overflow, zero implies underflow */
+	if (!finite(*result) || *result == 0.0)
 #endif
 		elog(ERROR, "exp() result is out of range");
 
-- 
cgit v1.2.3