---
upgrade:
  - |
    Changes how transpilation passes are handled in the C++ Controller classes
    so that each pass must be explicitly called. This allows for greater
    customization on when each pass should be called, and with what parameters.
    In particular this enables setting different parameters for the gate
    fusion optimization pass depending on the QasmController simulation method.
fixes:
  - |
    Fixes Controller classes so that the ReduceBarrier transpilation pass is
    applied first. This prevents barrier instructions from preventing truncation
    of unused qubits if the only instruction defined on them was a barrier.
  - |
    Disables gate fusion for the matrix product state simulation method as this
    was causing issues with incorrect results being returned in some cases.
