This is Linux and possibly Mac specific. FixDeps step does not have the proper dependencies and instead depends on every library, even one it is not relinking.
Reported on UDN (see additional URL for info).
1. Create a code project.
2. Build the editor for the said code project.
3. Build the editor for the said code project one more time.
4. Observe that "Target is up to date" is printed and no FixDeps steps happens.
5. Modify a source file in the new project's source file (just touch the file).
6. Build the editor for the said code project.
7. Observe that FixDeps step will be run and unrelated libraries will be relinked.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-37194 in the post.