Failed to compile utils-legato-mqtt , mqttclient code for wp7603 in Dev Studio

I am trying to compile the code mqttClient from github with source https://github.com/startwithsierra/utils-legato-mqtt for our application in MangOH Green with wp7603 module.
I tried to solve many errors in the code as it is compatible to older Legato Version. I am using Legato 18.01.0 .
I am stuck with one error which I am able to resolve it the screen shot is mentioned below.

I also tried in command line where the same problem repeated.

Thanks in advance, Please help me out to resolve this isssue. I am totally stuck here.

I’m not very familiar with that MQTT repository. Maybe @majditoumi can comment.

Another option is the use_paho_linux_version branch of the mangOH/MqttClient repository. https://github.com/mangOH/MqttClient/tree/use_paho_linux_version