For float4/8, remove errno checks for pow() and exp() because only some

platforms set errno, and we already have a check macro that detects
under/overflow, so there is no reason for platform-specific code
anymore.

diff --git a/src/backend/utils/adt/float.c b/src/backend/utils/adt/float.c
index dab6c35667f6dbaf7381d5fb2dbb906321d42835..2660bd3e31fc4fce01549b145d6b6881ccbac12e 100644 (file)
--- a/src/backend/utils/adt/float.c
+++ b/src/backend/utils/adt/float.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *   $PostgreSQL: pgsql/src/backend/utils/adt/float.c,v 1.135 2007/01/02 22:19:42 momjian Exp $
+ *   $PostgreSQL: pgsql/src/backend/utils/adt/float.c,v 1.136 2007/01/03 04:21:47 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1439,15 +1439,11 @@ dpow(PG_FUNCTION_ARGS)
                 errmsg("invalid argument for power function")));
 
    /*
-    * We must check both for errno getting set and for a NaN result, in order
-    * to deal with the vagaries of different platforms...
+    * pow() sets errno only on some platforms, depending on whether it
+    * follows _IEEE_, _POSIX_, _XOPEN_, or _SVID_, so, for consistency,
+    * we don't consult it and just do our check below.
     */
-   errno = 0;
    result = pow(arg1, arg2);
-   if (errno != 0 && !isinf(result))
-       ereport(ERROR,
-               (errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
-                errmsg("result is out of range")));
 
    CHECKFLOATVAL(result, isinf(arg1) || isinf(arg2), arg1 == 0);
    PG_RETURN_FLOAT8(result);
@@ -1464,15 +1460,11 @@ dexp(PG_FUNCTION_ARGS)
    float8      result;
 
    /*
-    * We must check both for errno getting set and for a NaN result, in order
-    * to deal with the vagaries of different platforms.
+    * exp() sets errno only on some platforms, depending on whether it
+    * follows _IEEE_, _POSIX_, _XOPEN_, or _SVID_, so, for consistency,
+    * we don't consult it and just do our check below.
     */
-   errno = 0;
    result = exp(arg1);
-   if (errno != 0 && !isinf(result))
-       ereport(ERROR,
-               (errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
-                errmsg("result is out of range")));
 
    CHECKFLOATVAL(result, isinf(arg1), false);
    PG_RETURN_FLOAT8(result);
@@ -1547,6 +1539,10 @@ dacos(PG_FUNCTION_ARGS)
    float8      arg1 = PG_GETARG_FLOAT8(0);
    float8      result;
 
+   /*
+    *  We use errno here because the trigonometric functions are cyclic
+    *  and hard to check for underflow.
+    */
    errno = 0;
    result = acos(arg1);
    if (errno != 0)