Get error message ''fatal: sha1 information is lacking or useless“ when apply a patch using ”git am -3"

Question

I am trying to apply a series of patches from 1 git repository to another git repository using git am -3 \"path to a patch\". I apply them in order, from patch 1-4, it works

Answer 1

Are you using submodules in your project?

There was a bug in git 1.7.12 to 1.8.1.2 where an updated submodule would cause a rebase (or patch) to fail with the error message:

fatal: sha1 information is lacking or useless

leaving the commit empty if applied.

More info here.

Updating git to version 1.8.4 solves this problem