Multiple modifiers error for stateSelect property

[carlj@…]

When validating the following model

model BouncingBall "Simple model of a bouncing ball"
  Ball ball1;
  model Ball
    Modelica.Mechanics.Translational.Components.SpringDamper springDamper1(c=250, d=0.6);
    Modelica.Mechanics.Translational.Components.Mass mass1(m=m, s.start=startpos, s.stateSelect=StateSelect.always);
    Modelica.Mechanics.Translational.Sources.Force force1;
    Modelica.Blocks.Sources.Constant const(k=-m*g);
    parameter Modelica.SIunits.Mass m=0.05 "Mass of the ball";
    parameter Modelica.SIunits.Acceleration g=Modelica.Constants.g_n "Acceleration constant";
    Modelica.Mechanics.Translational.Interfaces.Flange_a flange_a1;
    parameter Modelica.SIunits.Position startpos=2.5 "Start position for the ball";
    parameter Modelica.SIunits.Diameter d=0.067 "Ball diameter";
  equation 
    connect(springDamper1.flange_a,flange_a1);
    connect(springDamper1.flange_b,mass1.flange_a);
    connect(force1.flange,mass1.flange_a);
    connect(const.y,force1.f);
  end Ball;
  Modelica.Mechanics.Translational.Components.Fixed fixed1;
  Modelica.Mechanics.Translational.Components.ElastoGap elastoGap1(c=30000000000.0, d=100);
equation 
  connect(elastoGap1.flange_a,fixed1.flange);
  connect(ball1.flange_a1,elastoGap1.flange_b);
end BouncingBall;

you get the following error message

Multiple modifiers in same scope for element ball1.mass1.s.stateSelect: stateSelect = stateSelect, from calling scope: ball1.mass1, duplicates are: ball1.mass1.s.stateSelect: stateSelect = StateSelect.always.

even though the modifiers are not in the same scope scope.

[Martin Sjölund]

What is perhaps more surprising is that the elementName of this component is L (which matches the line numbers in the error-message). I wonder if this is simply the two modifications on s not being merged into s(start=..., stateSelect=...) and somehow break things.

[Per Östlund]

The issue seems to have been that submodifiers weren't merged correctly, since the issue boiled down to this:

model A
  Real x;
end A;

model B
  extends A(x(start = 0, nominal = 0));
end B;

model C
  B b(x(start = 0), x(nominal = 0));
end C;

I adapted some modifier handling functionality from NFInst and replaced the old code with it to provide better error messages, which also resolved this issue. The fix is in r21996.