Example fail to compile

[italocjs]

Example of PCF8523 fails to compile under platformio + esp32 (arduino framework)

.pio/libdeps/esp32dev/RTC/src/DS3231.cpp: In member function 'void DS3231::setEpoch(time_t, bool)':
.pio/libdeps/esp32dev/RTC/src/DS3231.cpp:614:19: error: 'UNIX_OFFSET' was not declared in this scope
   epoch = epoch - UNIX_OFFSET;
                   ^~~~~~~~~~~
.pio/libdeps/esp32dev/RTC/src/DS3231.cpp: In member function 'time_t DS3231::getEpoch(bool)':
.pio/libdeps/esp32dev/RTC/src/DS3231.cpp:750:12: error: 'UNIX_OFFSET' was not declared in this scope
   epoch += UNIX_OFFSET;
            ^~~~~~~~~~~
.pio/libdeps/esp32dev/RTC/src/DS1307.cpp: In member function 'void DS1307::setEpoch(time_t, bool)':
.pio/libdeps/esp32dev/RTC/src/DS1307.cpp:504:19: error: 'UNIX_OFFSET' was not declared in this scope
   epoch = epoch - UNIX_OFFSET;
                   ^~~~~~~~~~~
.pio/libdeps/esp32dev/RTC/src/DS3231.cpp: In member function 'uint8_t DS3231::getHours()':
.pio/libdeps/esp32dev/RTC/src/DS3231.cpp:271:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
.pio/libdeps/esp32dev/RTC/src/DS1307.cpp: In member function 'time_t DS1307::getEpoch(bool)':
.pio/libdeps/esp32dev/RTC/src/DS1307.cpp:535:12: error: 'UNIX_OFFSET' was not declared in this scope
   epoch += UNIX_OFFSET;
            ^~~~~~~~~~~
*** [.pio\build\esp32dev\libdcf\RTC\DS3231.cpp.o] Error 1
.pio/libdeps/esp32dev/RTC/src/DS1307.cpp: In member function 'uint8_t DS1307::getHours()':
.pio/libdeps/esp32dev/RTC/src/DS1307.cpp:234:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
*** [.pio\build\esp32dev\libdcf\RTC\DS1307.cpp.o] Error 1
======================================================= [FAILED] Took 5.80 seconds =======================================================


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[Den2016]

the author does not know that there are other boards besides arduino. Just comment out two lines in I2C_RTC.h
Line 16 and 18.
The author also believes that there can be more than two time formats and therefore we get warnings when compiling

/*-----------------------------------------------------------
getHours
-----------------------------------------------------------*/
uint8_t DS1307::getHours()
{
	uint8_t hour;
	bool h_mode;
	h_mode = getHourMode();
	Wire.beginTransmission(DS1307_ADDR);
	Wire.write(0x02);  // Hour Register
	Wire.endTransmission();
	Wire.requestFrom(DS1307_ADDR, 1);
	hour = Wire.read();
	if (h_mode == CLOCK_H24)
	{
		return (bcd2bin(hour));
	}
	else //_if (h_mode == CLOCK_H12)_
	{
		bitClear(hour, 5);
		bitClear(hour, 6);
		return (bcd2bin(hour));
	}
}

just comment out condition after else. Same warnings for DS3231 & PCF8523