diff --git a/cli/command/image/build.go b/cli/command/image/build.go
index 27b6cafd87..dd7510c440 100644
--- a/cli/command/image/build.go
+++ b/cli/command/image/build.go
@@ -34,8 +34,6 @@ import (
 	"github.com/spf13/cobra"
 )
 
-var errStdinConflict = errors.New("invalid argument: can't use stdin for both build context and dockerfile")
-
 type buildOptions struct {
 	context        string
 	dockerfileName string
@@ -189,7 +187,7 @@ func runBuild(dockerCli command.Cli, options buildOptions) error {
 
 	if options.dockerfileFromStdin() {
 		if options.contextFromStdin() {
-			return errStdinConflict
+			return errors.New("invalid argument: can't use stdin for both build context and dockerfile")
 		}
 		dockerfileCtx = dockerCli.In()
 	}