I am new to arduino and to ESP module, my task is to make ESP8266 to act as Gateway for the communication between two devices. so when I transfer a data, it need to be transferred through the gateway to the other PC. I installed arduino and installed Mysensors library in it.I am using esp8266 gateway example, while compiling it is showing the error

Arduino: 1.8.7 (Windows 10), Board: "Generic ESP8266 Module, 80 MHz, Flash, ck, 26 MHz, 40MHz, QIO, 512K (no SPIFFS), 2, v2 Lower Memory, Disabled, None, Only Sketch, 9600"

Build options changed, rebuilding all
In file included from C:\Users\kishor.babu\Documents\Arduino\libraries\MySensors/MySensors.h:420:0,

                 from C:\Users\kishor.babu\Documents\Arduino\libraries\MySensors\examples\GatewayESP8266\GatewayESP8266.ino:118:

C:\Users\kishor.babu\Documents\Arduino\libraries\MySensors/hal/architecture/ESP8266/MyMainESP8266.cpp:57:53: error: declaration of C function 'void ets_update_cpu_frequency(int)' conflicts with

 extern "C" void ets_update_cpu_frequency(int freqmhz);

                                                     ^

In file included from C:\Users\kishor.babu\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\2.4.2\cores\esp8266/pgmspace.h:10:0,

                 from C:\Users\kishor.babu\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\2.4.2\cores\esp8266/Arduino.h:256,

                 from sketch\GatewayESP8266.ino.cpp:1:

C:\Users\kishor.babu\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\2.4.2/tools/sdk/include/ets_sys.h:218:6: error: previous declaration 'void ets_update_cpu_frequency(uint32_t)' here

 void ets_update_cpu_frequency(uint32_t ticks_per_us);

      ^

exit status 1
Error compiling for board Generic ESP8266 Module.

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