Merge pull request #858 from SciML/myb/ss

Minor fixes

Author: ChrisRackauckas

src/systems/abstractsystem.jl

@@ -481,7 +481,6 @@ topological sort of the observed equations.
 """
 function structural_simplify(sys::AbstractSystem)
     sys = tearing(alias_elimination(sys))
-    s = structure(sys)
     fullstates = [get_reduced_states(sys); states(sys)]
     @set! sys.observed = topsort_equations(observed(sys), fullstates)
     return sys

src/systems/diffeqs/odesystem.jl

@@ -222,6 +222,7 @@ function flatten(sys::ODESystem)
                          observed=observed(sys),
                          default_u0=default_u0(sys),
                          default_p=default_p(sys),
+                         name=nameof(sys),
                         )
     end
 end

src/systems/nonlinear/nonlinearsystem.jl

@@ -300,6 +300,7 @@ function flatten(sys::NonlinearSystem)
                                observed=observed(sys),
                                default_u0=default_u0(sys),
                                default_p=default_p(sys),
+                               name=nameof(sys),
                               )
     end
 end