================
Comment at: lib/DebugInfo/DWARFContext.cpp:415
@@ -415,2 +414,3 @@
+      std::upper_bound(CUs.begin(), CUs.end(), Offset, OffsetComparator());
   if (CU != CUs.end()) {
     return CU->get();
----------------
You still need to check that Offset you're looking for is inside the CU.
http://reviews.llvm.org/D5262