Wrong order of generated structs for generation of structs containing anonymous unions

[martinkosch]

Hi everyone,
thank you for the amazing package so far!

I think I encountered a small (but annoying) bug in the current master branch: the generation of structs containing anonymous unions prints the corresponding Julia union wrapper struct after the original struct definition.

In my case, the C struct

typedef struct {
      enum NodeIdType id_type;
      union {
          UInt32     numeric;
          Guid       guid;
      } id;
  } NodeId;

results in the generated code

mutable struct NodeId
    id_type::NodeIdType
    id::__JL_Ctag_295
    NodeId() = new()
end
...
struct __JL_Ctag_295
    data::NTuple{16, UInt8}
end

leading to

ERROR: LoadError: LoadError: UndefVarError: __JL_Ctag_295 not defined

If I am not missing something, the problem can be solved by changing the order of the generated structs.

[Gnimuc]

This can be fixed by storing the indices of those nested records in the option Dict and then add a pass to print them right after the prologue printer pass.

[martinkosch]

Printing the nested records right after the prologue does not solve the problem though if the nested records themselves or their generated getproperty/setproperty! functions depend on other structs that are defined after the prologue. The best guess for a suitable position is probably right before the struct that contains the anonymous union.

[Gnimuc]

You're right. A better way is to add the indices of those inner nested structs to the nested struct. In this way, the order will be sorted automatically in the toposort pass.