From ca97dad7a249af42813510019003cd9bc784c481 Mon Sep 17 00:00:00 2001
From: Andrew Glaude <andrew.glaude@datadoghq.com>
Date: Mon, 12 Jun 2023 15:29:51 -0400
Subject: [PATCH] tracer: move reflect nil error check to WithError to never
 set a bad nil value

---
 ddtrace/tracer/option.go | 4 ++++
 ddtrace/tracer/span.go   | 2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/ddtrace/tracer/option.go b/ddtrace/tracer/option.go
index 9dcbd1adb6..47dbc7d4ca 100644
--- a/ddtrace/tracer/option.go
+++ b/ddtrace/tracer/option.go
@@ -15,6 +15,7 @@ import (
 	"net/url"
 	"os"
 	"path/filepath"
+	"reflect"
 	"runtime"
 	"strconv"
 	"strings"
@@ -892,6 +893,9 @@ func FinishTime(t time.Time) FinishOption {
 // err to set tags such as the error message, error type and stack trace. It has
 // no effect if the error is nil.
 func WithError(err error) FinishOption {
+	if err == nil || reflect.ValueOf(err).IsNil() {
+		return func(_ *ddtrace.FinishConfig) {}
+	}
 	return func(cfg *ddtrace.FinishConfig) {
 		cfg.Error = err
 	}
diff --git a/ddtrace/tracer/span.go b/ddtrace/tracer/span.go
index 128f6666f4..e926d5eba9 100644
--- a/ddtrace/tracer/span.go
+++ b/ddtrace/tracer/span.go
@@ -424,7 +424,7 @@ func (s *span) Finish(opts ...ddtrace.FinishOption) {
 		if !cfg.FinishTime.IsZero() {
 			t = cfg.FinishTime.UnixNano()
 		}
-		if cfg.Error != nil && !reflect.ValueOf(cfg.Error).IsNil() {
+		if cfg.Error != nil {
 			s.Lock()
 			s.setTagError(cfg.Error, errorConfig{
 				noDebugStack: cfg.NoDebugStack,