Summary

The value is not stored for the HORSE_HAPPY_IF_FED_WITHIN macro function instead it stores the storage pointer which is 0 ==> slot 0.

Vulnerability Details

Impact

Since the value is set to 0 which is the 0th slot storage pointer rather than the supposed 24-hour timestamp in seconds when you feed a horse, the horseIdToFedTimeStamp[horseId] is set to the block.timestamp when you feed it but checking that the horse has indeed been fed will reveal a misleading result because we compare 0 to 24 hours in seconds which will return false telling us the horse has not been fed rather than the opposite.

Tools Used

Manual review

Recommendations

Fix the macro function to store the value to compare against 0x0000000000000000000000000000000000000000000000000000000000015180 instead of 0.