diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index fe6c6f8a05a..1c4f9ac04e6 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -6240,13 +6240,15 @@ parse_real(const char *value, double *result, int flags, const char **hintmsg)
 	if (hintmsg)
 		*hintmsg = NULL;
 
-	errno = 0;
 	val = strtod(value, &endptr);
+	if (endptr == value)
+		return false;			/* no HINT for syntax error */
 
-	if (endptr == value || errno == ERANGE)
-		return false;			/* no HINT for these cases */
-
-	/* reject NaN (infinities will fail range checks later) */
+	/*
+	 * We ignore strtod's errno, so that out-of-range inputs will just result
+	 * in zero or infinity values.  Subsequent range checks will reject those
+	 * if necessary.  We do need to reject NaN explicitly, however.
+	 */
 	if (isnan(val))
 		return false;			/* treat same as syntax error; no HINT */