Your clang TSA patches

[Stefan Hajnoczi]

Hi Marc-André,
clang's Thread Safety Analysis is being used more in the QEMU block
layer and a few limitations have been hit:
1. Mutexes that are struct fields are not supported (only global mutexes work).
2. Analysis does not extend across function pointers. See
GRAPH_RDLOCK_PTR for a workaround that is currently used.

(There was a third limitation that I don't remember. Maybe Kevin remembers.)

I heard you had clang or LLVM patches in that past that improve TSA.
Did your patches address these things? Any idea how hard it is to fix
these limitations?

Thanks,
Stefan