Thanks. That was indeed the problem. It compiles fine!

Re: ESP8266 Gateway
I do have a similar problem with the MySensors GateWayESP8266. I have the latest version of MySensors ,the latest version of
Arduino IDE (1.8.15) and the latest version of ESP8266 boards (3.0.0) and still do I run into compile erros during Validate.
I run into 4 errors when I validate with MY_DEBUG commented, otherwise I will have more then 60 pages of errors.

Can anybody advice me where to look and how to solve?

Arduino:1.8.15 (Windows Store 1.8.49.0) (Windows 10), Board:"Generic ESP8266 Module, 80 MHz, Flash, Disabled (new aborts on oom), Disabled, All SSL ciphers (most compatible), 32KB cache + 32KB IRAM (balanced), Use pgm_read macros for IRAM/PROGMEM, dtr (aka nodemcu), 26 MHz, 40MHz, DOUT (compatible), 1MB (FS:64KB OTA:~470KB), 2, nonos-sdk 2.2.1+100 (190703), v2 Lower Memory, Disabled, None, Only Sketch, 115200"

OUTPUT:

In file included from c:\users\mathi\onedrive\documenten\arduinodata\packages\esp8266\tools\xtensa-lx106-elf-gcc\3.0.0-newlib4.0.0-gnu23-48f7b08\xtensa-lx106-elf\include\assert.h:10,

             from c:\users\mathi\onedrive\documenten\arduinodata\packages\esp8266\tools\xtensa-lx106-elf-gcc\3.0.0-newlib4.0.0-gnu23-48f7b08\xtensa-lx106-elf\include\sys\reent.h:503,

             from c:\users\mathi\onedrive\documenten\arduinodata\packages\esp8266\tools\xtensa-lx106-elf-gcc\3.0.0-newlib4.0.0-gnu23-48f7b08\xtensa-lx106-elf\include\stdlib.h:18,

             from c:\users\mathi\onedrive\documenten\arduinodata\packages\esp8266\tools\xtensa-lx106-elf-gcc\3.0.0-newlib4.0.0-gnu23-48f7b08\xtensa-lx106-elf\include\c++\10.2.0\cstdlib:75,

             from c:\users\mathi\onedrive\documenten\arduinodata\packages\esp8266\tools\xtensa-lx106-elf-gcc\3.0.0-newlib4.0.0-gnu23-48f7b08\xtensa-lx106-elf\include\c++\10.2.0\stdlib.h:36,

             from C:\Users\mathi\OneDrive\Documenten\ArduinoData\packages\esp8266\hardware\esp8266\3.0.0\cores\esp8266/Arduino.h:27,

             from sketch\MySensors_GatewayESP8266_v01.ino.cpp:1:

C:\Users\mathi\OneDrive\Documenten\Arduino\libraries\MySensors/core/MyProtocol.cpp: In function 'char* protocolMyMessage2Serial(MyMessage&)':

C:\Users\mathi\OneDrive\Documenten\Arduino\libraries\MySensors/core/MyProtocol.cpp:94:28: error: expected ')' before '__INT8'

94 | PSTR("%" PRIu8 ";%" PRIu8 ";%" PRIu8 ";%" PRIu8 ";%" PRIu8 ";%s\n"), message.getSender(),

  |                            ^~~~~

C:\Users\mathi\OneDrive\Documenten\Arduino\libraries\MySensors/core/MyProtocol.cpp:94:19: note: to match this '('

94 | PSTR("%" PRIu8 ";%" PRIu8 ";%" PRIu8 ";%" PRIu8 ";%" PRIu8 ";%s\n"), message.getSender(),

  |                   ^~~~

C:\Users\mathi\OneDrive\Documenten\Arduino\libraries\MySensors/core/MyProtocol.cpp: In function 'char* protocolMyMessage2MQTT(const char*, MyMessage&)':

C:\Users\mathi\OneDrive\Documenten\Arduino\libraries\MySensors/core/MyProtocol.cpp:103:31: error: expected ')' before '__INT8'

103 | PSTR("%s/%" PRIu8 "/%" PRIu8 "/%" PRIu8 "/%" PRIu8 "/%" PRIu8 ""), prefix,

  |                               ^~~~~

C:\Users\mathi\OneDrive\Documenten\Arduino\libraries\MySensors/core/MyProtocol.cpp:103:19: note: to match this '('

103 | PSTR("%s/%" PRIu8 "/%" PRIu8 "/%" PRIu8 "/%" PRIu8 "/%" PRIu8 ""), prefix,

  |                   ^~~~

exit status 1

Fout bij het compileren voor board Generic ESP8266 Module

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