After having several hard kernel crashes, some of my files ended up empty on my disk. I then got errors like:
error: object file .git/objects/81/b43db0dadcafe18eef75c60c57cc496d523d83 is empty error: object file .git/objects/fb/9b5b3daa56c7833be66f0eaac2b5a906474627 is empty
I can recommend this Wiki page on kernel.org which tells how recovery basically should be done. This post shows some of those steps a bit more “hands-on”. I started with moving this corrupt (empty) object away, and then got this message when doing some git operations:
fatal: unable to read 81b43db0dadcafe18eef75c60c57cc496d523d83