Hmm...  Looks like a unified diff to me...
The text leading up to this was:
--------------------------
|diff --git a/config.def.h b/config.def.h
|index 9855e21..a2020bb 100644
|--- a/config.def.h
|+++ b/config.def.h
--------------------------
Patching file config.def.h using Plan A...