diff --git a/README.md b/README.md
index 2e953f5aae..6f9178cac1 100644
--- a/README.md
+++ b/README.md
@@ -24,6 +24,7 @@ Gin is a web framework written in Go (Golang). It features a martini-like API wi
   - [Benchmarks](#benchmarks)
   - [Gin v1. stable](#gin-v1-stable)
   - [Build with jsoniter/go-json](#build-with-json-replacement)
+  - [Build without `MsgPack` rendering feature](#build-without-msgpack-rendering-feature)
   - [API Examples](#api-examples)
     - [Using GET, POST, PUT, PATCH, DELETE and OPTIONS](#using-get-post-put-patch-delete-and-options)
     - [Parameters in path](#parameters-in-path)
@@ -195,6 +196,16 @@ $ go build -tags=jsoniter .
 $ go build -tags=go_json .
 ```
 
+## Build without `MsgPack` rendering feature
+
+Gin enables `MsgPack` rendering feature by default. But you can disable this feature by specifying `nomsgpack` build tag.
+
+```sh
+$ go build -tags=nomsgpack .
+```
+
+This is useful to reduce the binary size of executable files. See the [detail information](https://github.com/gin-gonic/gin/pull/1852).
+
 ## API Examples
 
 You can find a number of ready-to-run examples at [Gin examples repository](https://github.com/gin-gonic/examples).
@@ -930,7 +941,7 @@ func main() {
 	route.GET("/:name/:id", func(c *gin.Context) {
 		var person Person
 		if err := c.ShouldBindUri(&person); err != nil {
-			c.JSON(400, gin.H{"msg": err})
+			c.JSON(400, gin.H{"msg": err.Error()})
 			return
 		}
 		c.JSON(200, gin.H{"name": person.Name, "uuid": person.ID})
diff --git a/logger.go b/logger.go
index d361b74d32..22138a8d30 100644
--- a/logger.go
+++ b/logger.go
@@ -138,8 +138,7 @@ var defaultLogFormatter = func(param LogFormatterParams) string {
 	}
 
 	if param.Latency > time.Minute {
-		// Truncate in a golang < 1.8 safe way
-		param.Latency = param.Latency - param.Latency%time.Second
+		param.Latency = param.Latency.Truncate(time.Second)
 	}
 	return fmt.Sprintf("[GIN] %v |%s %3d %s| %13v | %15s |%s %-7s %s %#v\n%s",
 		param.TimeStamp.Format("2006/01/02 - 15:04:05"),