ObjFW  Diff

		tm.tm_isdst = -1;

		if (of_strptime([string UTF8String], [format UTF8String],
		    &tm) == NULL)
			@throw [OFInvalidFormatException
			    exceptionWithClass: isa];

#ifdef STRUCT_TM_HAS_TM_GMTOFF
		if (tm.tm_gmtoff != 0)
			@throw [OFInvalidFormatException
			    exceptionWithClass: isa];
#endif

		/* Years */
		seconds = (int64_t)(tm.tm_year - 70) * 31536000;
		/* Days of leap years, excluding the year to look at */
		seconds += (((tm.tm_year + 1899) / 4) - 492) * 86400;
		seconds -= (((tm.tm_year + 1899) / 100) - 19) * 86400;
		seconds += (((tm.tm_year + 1899) / 400) - 4) * 86400;
		/* Leap day */