Problem uploading - avrdude mystery error

I was working with the arduino and when i uploaded a code so it displayed-

Arduino: 1.8.2 (Windows 7), Board: "Arduino Leonardo"

WARNING: Category 'Real-time clock' in library DS3231 is not valid. Setting to 'Uncategorized'
Sketch uses 4112 bytes (14%) of program storage space. Maximum is 28672 bytes.
Global variables use 147 bytes (5%) of dynamic memory, leaving 2413 bytes for local variables. Maximum is 2560 bytes.
Found programmer: Id = ""; type =

What could be the possible reason for this??

What can I do???

It is just a warning that the library you have is not good.

But thats not the whole error message. make sure you have VERBOSE turned on in preferences.

Also when posting error messages please use the code tags ( </> )