diff --git a/binding/binding_test.go b/binding/binding_test.go
index a9f8b9e3..e33bdbf6 100644
--- a/binding/binding_test.go
+++ b/binding/binding_test.go
@@ -1403,6 +1403,26 @@ func TestPlainBinding(t *testing.T) {
 	require.NoError(t, p.Bind(req, ptr))
 }
 
+func TestPlainBindingBindBody(t *testing.T) {
+	p := Plain
+
+	var s string
+	require.NoError(t, p.BindBody([]byte("test string"), &s))
+	assert.Equal(t, "test string", s)
+
+	var bs []byte
+	require.NoError(t, p.BindBody([]byte("test []byte"), &bs))
+	assert.Equal(t, []byte("test []byte"), bs)
+
+	var i int
+	require.Error(t, p.BindBody([]byte("test fail"), &i))
+
+	require.NoError(t, p.BindBody([]byte(""), nil))
+
+	var ptr *string
+	require.NoError(t, p.BindBody([]byte(""), ptr))
+}
+
 func testProtoBodyBindingFail(t *testing.T, b Binding, name, path, badPath, body, badBody string) {
 	assert.Equal(t, name, b.Name())
 
diff --git a/context_test.go b/context_test.go
index 41694585..3ea410d9 100644
--- a/context_test.go
+++ b/context_test.go
@@ -40,6 +40,12 @@ var _ context.Context = (*Context)(nil)
 
 var errTestRender = errors.New("TestRender")
 
+type errReader int
+
+func (errReader) Read(p []byte) (n int, err error) {
+	return 0, errors.New("test error")
+}
+
 // Unit tests TODO
 // func (c *Context) File(filepath string) {
 // func (c *Context) Negotiate(code int, config Negotiate) {
@@ -2947,6 +2953,17 @@ func TestContextGetRawData(t *testing.T) {
 	assert.Equal(t, "Fetch binary post data", string(data))
 }
 
+func TestContextGetRawDataNilBody(t *testing.T) {
+	c, _ := CreateTestContext(httptest.NewRecorder())
+	c.Request, _ = http.NewRequest(http.MethodPost, "/", nil)
+	c.Request.Body = nil
+
+	data, err := c.GetRawData()
+	require.Error(t, err)
+	assert.Nil(t, data)
+	assert.Equal(t, "cannot read nil body", err.Error())
+}
+
 func TestContextRenderDataFromReader(t *testing.T) {
 	w := httptest.NewRecorder()
 	c, _ := CreateTestContext(w)
@@ -3535,6 +3552,24 @@ func TestContextSetCookieData(t *testing.T) {
 		setCookie := c.Writer.Header().Get("Set-Cookie")
 		assert.Contains(t, setCookie, "SameSite=None")
 	})
+
+	// Test that SameSiteDefaultMode is replaced with context's SameSite
+	t.Run("SameSiteDefaultMode is replaced with context SameSite", func(t *testing.T) {
+		c, _ := CreateTestContext(httptest.NewRecorder())
+		c.SetSameSite(http.SameSiteLaxMode)
+		cookie := &http.Cookie{
+			Name:     "user",
+			Value:    "gin",
+			Path:     "/",
+			Domain:   "localhost",
+			Secure:   true,
+			HttpOnly: true,
+			SameSite: http.SameSiteDefaultMode,
+		}
+		c.SetCookieData(cookie)
+		setCookie := c.Writer.Header().Get("Set-Cookie")
+		assert.Contains(t, setCookie, "user=gin")
+	})
 }
 
 func TestGetMapFromFormData(t *testing.T) {
@@ -3752,3 +3787,43 @@ func BenchmarkGetMapFromFormData(b *testing.B) {
 		})
 	}
 }
+
+func TestInitFormCacheParseMultipartFormError(t *testing.T) {
+	c, _ := CreateTestContext(httptest.NewRecorder())
+	c.Request, _ = http.NewRequest(http.MethodPost, "/", strings.NewReader("test"))
+	c.Request.Header.Set("Content-Type", "multipart/form-data; boundary=invalid")
+	c.engine.MaxMultipartMemory = -1
+	c.initFormCache()
+	assert.NotNil(t, c.formCache)
+}
+
+func TestFormFileParseMultipartFormError(t *testing.T) {
+	c, _ := CreateTestContext(httptest.NewRecorder())
+	c.Request, _ = http.NewRequest(http.MethodPost, "/", strings.NewReader("test"))
+	c.Request.Header.Set("Content-Type", "multipart/form-data; boundary=invalid")
+	c.engine.MaxMultipartMemory = -1
+	_, err := c.FormFile("file")
+	require.Error(t, err)
+}
+
+func TestShouldBindBodyWithTypeAssertionFailure(t *testing.T) {
+	w := httptest.NewRecorder()
+	c, _ := CreateTestContext(w)
+	c.Request, _ = http.NewRequest(http.MethodPost, "http://example.com", strings.NewReader(`{"foo":"FOO"}`))
+	c.Set(BodyBytesKey, "not a byte slice")
+	var obj struct {
+		Foo string `json:"foo"`
+	}
+	require.NoError(t, c.ShouldBindBodyWith(&obj, binding.JSON))
+	assert.Equal(t, "FOO", obj.Foo)
+}
+
+func TestShouldBindBodyWithReadError(t *testing.T) {
+	w := httptest.NewRecorder()
+	c, _ := CreateTestContext(w)
+	c.Request, _ = http.NewRequest(http.MethodPost, "http://example.com", errReader(0))
+	var obj struct {
+		Foo string `json:"foo"`
+	}
+	require.Error(t, c.ShouldBindBodyWith(&obj, binding.JSON))
+}
diff --git a/gin.go b/gin.go
index 2e033bf3..cae96c7e 100644
--- a/gin.go
+++ b/gin.go
@@ -96,6 +96,9 @@ type Engine struct {
 	// (used for routing HTTP requests) happens only once, even if called multiple times concurrently.
 	routeTreesUpdated sync.Once
 
+	// mu protects concurrent access to trees
+	mu sync.RWMutex
+
 	// RedirectTrailingSlash enables automatic redirection if the current route can't be matched but a
 	// handler for the path with (without) the trailing slash exists.
 	// For example if /foo/ is requested but a route only exists for /foo, the
@@ -368,6 +371,9 @@ func (engine *Engine) addRoute(method, path string, handlers HandlersChain) {
 
 	debugPrintRoute(method, path, handlers)
 
+	engine.mu.Lock()
+	defer engine.mu.Unlock()
+
 	root := engine.trees.get(method)
 	if root == nil {
 		root = new(node)
@@ -388,6 +394,8 @@ func (engine *Engine) addRoute(method, path string, handlers HandlersChain) {
 // Routes returns a slice of registered routes, including some useful information, such as:
 // the http method, path, and the handler name.
 func (engine *Engine) Routes() (routes RoutesInfo) {
+	engine.mu.RLock()
+	defer engine.mu.RUnlock()
 	for _, tree := range engine.trees {
 		routes = iterate("", tree.method, routes, tree.root)
 	}
diff --git a/gin_test.go b/gin_test.go
index 43c9494d..752820b1 100644
--- a/gin_test.go
+++ b/gin_test.go
@@ -1067,6 +1067,38 @@ func TestLiteralColonWithHTTPServer(t *testing.T) {
 	assert.Contains(t, w2.Body.String(), "foo")
 }
 
+func TestConcurrentAddRouteAndRoutes(t *testing.T) {
+	router := New()
+
+	done := make(chan bool)
+
+	for i := 0; i < 10; i++ {
+		go func(n int) {
+			router.GET(fmt.Sprintf("/route%d", n), func(c *Context) {
+				c.String(http.StatusOK, fmt.Sprintf("route%d", n))
+			})
+			router.POST(fmt.Sprintf("/route%d", n), func(c *Context) {
+				c.String(http.StatusOK, fmt.Sprintf("route%d", n))
+			})
+			done <- true
+		}(i)
+	}
+
+	for i := 0; i < 10; i++ {
+		go func() {
+			_ = router.Routes()
+			done <- true
+		}()
+	}
+
+	for i := 0; i < 20; i++ {
+		<-done
+	}
+
+	routes := router.Routes()
+	assert.Len(t, routes, 20)
+}
+
 // Test that updateRouteTrees is called only once
 func TestUpdateRouteTreesCalledOnce(t *testing.T) {
 	SetMode(TestMode)
@@ -1084,3 +1116,39 @@ func TestUpdateRouteTreesCalledOnce(t *testing.T) {
 		assert.Equal(t, "ok", w.Body.String())
 	}
 }
+
+func TestServeErrorWritten(t *testing.T) {
+	SetMode(TestMode)
+	router := New()
+	router.Use(func(c *Context) {
+		c.Writer.WriteHeader(http.StatusNotFound)
+		_, _ = c.Writer.Write([]byte("custom error"))
+		c.Next()
+	})
+	router.NoRoute(func(c *Context) {
+		c.Next()
+	})
+
+	w := httptest.NewRecorder()
+	req, _ := http.NewRequest(http.MethodGet, "/notfound", nil)
+	router.ServeHTTP(w, req)
+	assert.Equal(t, http.StatusNotFound, w.Code)
+	assert.Equal(t, "custom error", w.Body.String())
+}
+
+func TestServeErrorStatusMismatch(t *testing.T) {
+	SetMode(TestMode)
+	router := New()
+	router.Use(func(c *Context) {
+		c.Writer.WriteHeader(http.StatusInternalServerError)
+		c.Next()
+	})
+	router.NoRoute(func(c *Context) {
+		c.Next()
+	})
+
+	w := httptest.NewRecorder()
+	req, _ := http.NewRequest(http.MethodGet, "/notfound", nil)
+	router.ServeHTTP(w, req)
+	assert.Equal(t, http.StatusInternalServerError, w.Code)
+}
diff --git a/logger_test.go b/logger_test.go
index 53d0df95..2d22c6e1 100644
--- a/logger_test.go
+++ b/logger_test.go
@@ -329,6 +329,7 @@ func TestColorForLatency(t *testing.T) {
 	assert.Equal(t, white, colorForLantency(time.Millisecond*20), "20ms should be white")
 	assert.Equal(t, green, colorForLantency(time.Millisecond*150), "150ms should be green")
 	assert.Equal(t, cyan, colorForLantency(time.Millisecond*250), "250ms should be cyan")
+	assert.Equal(t, blue, colorForLantency(time.Millisecond*400), "400ms should be blue")
 	assert.Equal(t, yellow, colorForLantency(time.Millisecond*600), "600ms should be yellow")
 	assert.Equal(t, magenta, colorForLantency(time.Millisecond*1500), "1.5s should be magenta")
 	assert.Equal(t, red, colorForLantency(time.Second*3), "other things should be red")
diff --git a/utils_test.go b/utils_test.go
index 893ebc88..168b1850 100644
--- a/utils_test.go
+++ b/utils_test.go
@@ -13,6 +13,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 func init() {
@@ -145,6 +146,15 @@ func TestMarshalXMLforH(t *testing.T) {
 	assert.Error(t, e)
 }
 
+func TestMarshalXMLforHSuccess(t *testing.T) {
+	h := H{
+		"key": "value",
+	}
+	data, err := xml.Marshal(h)
+	require.NoError(t, err)
+	assert.Contains(t, string(data), "<key>value</key>")
+}
+
 func TestIsASCII(t *testing.T) {
 	assert.True(t, isASCII("test"))
 	assert.False(t, isASCII("🧡💛💚💙💜"))