Program: 84557
Project: 84557
Buggy source:
@Override public float getSignatureMatch(Name name,IValue instance,IArguments arguments){
  if (name != null && name != this.name) {
    return 0;
  }
  if ((this.modifiers & Modifiers.SYNTHETIC) != 0) {
    return 0;
  }
  if (arguments == null) {
    return 1;
  }
  if (instance == null && this.modifiers == Modifiers.PREFIX) {
    float m=arguments.getFirstValue().getTypeMatch(this.theClass.getType());
    if (m == 0) {
      return 0;
    }
    return 1 + m;
  }
  int parIndex=0;
  int match=1;
  int argumentCount=arguments.size();
  if (instance != null) {
    int mod=(this.modifiers & Modifiers.INFIX);
    if (mod != 0 && instance.valueTag() == IValue.CLASS_ACCESS) {
      instance=null;
    }
 else     if (mod == Modifiers.INFIX) {
      IType t2=this.parameters[0].getType();
      float m=instance.getTypeMatch(t2);
      if (m == 0) {
        return 0;
      }
      match+=m;
      parIndex=1;
    }
  }
  if ((this.modifiers & Modifiers.VARARGS) != 0) {
    int len=this.parameterCount - 1 - parIndex;
    float m;
    for (int i=parIndex; i < len; i++) {
      IParameter par=this.parameters[i + parIndex];
      m=arguments.getTypeMatch(i,par);
      if (m == 0) {
        return 0;
      }
      match+=m;
    }
    m=arguments.getVarargsTypeMatch(len,this.parameters[len + parIndex]);
    if (m == 0) {
      return 0;
    }
    return match + m;
  }
  int len=this.parameterCount - parIndex;
  if (argumentCount > len) {
    return 0;
  }
  for (int i=0; i < len; i++) {
    IParameter par=this.parameters[i + parIndex];
    float m=arguments.getTypeMatch(i,par);
    if (m == 0) {
      return 0;
    }
    match+=m;
  }
  return match;
}

Fixed version (ground truth):
@Override public float getSignatureMatch(Name name,IValue instance,IArguments arguments){
  if (name != null && name != this.name) {
    return 0;
  }
  if (arguments == null) {
    return 1;
  }
  if (instance == null && this.modifiers == Modifiers.PREFIX) {
    float m=arguments.getFirstValue().getTypeMatch(this.theClass.getType());
    if (m == 0) {
      return 0;
    }
    return 1 + m;
  }
  int parIndex=0;
  int match=1;
  int argumentCount=arguments.size();
  if (instance != null) {
    int mod=(this.modifiers & Modifiers.INFIX);
    if (mod != 0 && instance.valueTag() == IValue.CLASS_ACCESS) {
      instance=null;
    }
 else     if (mod == Modifiers.INFIX) {
      IType t2=this.parameters[0].getType();
      float m=instance.getTypeMatch(t2);
      if (m == 0) {
        return 0;
      }
      match+=m;
      parIndex=1;
    }
  }
  if ((this.modifiers & Modifiers.VARARGS) != 0) {
    int len=this.parameterCount - 1 - parIndex;
    float m;
    for (int i=parIndex; i < len; i++) {
      IParameter par=this.parameters[i + parIndex];
      m=arguments.getTypeMatch(i,par);
      if (m == 0) {
        return 0;
      }
      match+=m;
    }
    m=arguments.getVarargsTypeMatch(len,this.parameters[len + parIndex]);
    if (m == 0) {
      return 0;
    }
    return match + m;
  }
  int len=this.parameterCount - parIndex;
  if (argumentCount > len) {
    return 0;
  }
  for (int i=0; i < len; i++) {
    IParameter par=this.parameters[i + parIndex];
    float m=arguments.getTypeMatch(i,par);
    if (m == 0) {
      return 0;
    }
    match+=m;
  }
  return match;
}