[llvm-dev] Problem with tbaa sporadically crashing on me

[Nat! via llvm-dev]

I migrated my clang compiler fork from 3.9 to 4.0.0, seemingly without a
hitch.

Unfortunately I now get sporadically this error, which I have trouble
reproducing:

```
Did not see access type in access path!
  %2 = load %"struct.NSDate::p.timeIntervalSince1970"*,
%"struct.NSDate::p.timeIntervalSince1970"** %_param.addr, align 8, !tbaa !34
!34 = !{!35, !9, i64 0}
fatal error: error in backend: Broken function found, compilation aborted!
```

What does the above error generally point too. As far as I can deduce
the problem is related to tbaa and it doesn't seem to be happy about the
!34 line ? I don't know anything about tbaa, to be frank. Could I be
emitting incomplete information in my function calls ? I don't even
really know what "access type" and "access path" means?

Ciao
   Nat!

P.S. It is kinda sad to see, that running the clang analyzer in Xcode on
clang 4.0.0 itself produces ~80 issues, some of which look like bona
fide bugs to me.