[cfe-dev] Cleaning up the representation of Decls in the AST

[Argiris Kirtzidis]

Argiris Kirtzidis wrote:
> Ted Kremenek wrote:
>> Another reason that having types own Decls is that it really makes 
>> things much more difficult for clients that wish to modify the AST.  
>> When is a Decl owned by a type?  With the idea you propose, a 
>> DeclStmt might own a TypeDecl if it isn't a RecordDecl, but in the 
>> case of a RecordType the type would own it.  There is also the 
>> problem that we now have multiple RecordDecls for a given 
>> RecordType.  Does the RecordType own all of those RecordDecls?  This 
>> actually makes manipulation of the AST really tricky and error prone.
>
> To be more clear, the idea is that TypeDecls are owned by Types, and 
> only one RecordDecl would be created.
> Can clients modify the AST without involving Types ? Assuming one 
> RecordDecl in the AST is replaced with another, what about the 
> RecordType the refers to it ?
> My point is that if the DeclGroup owns the RecordDecl, the Type will 
> still need to be updated. If the Type owns the the RecordDecl you may 
> only need to update the Type.

Also, about modifying the AST: assuming you want to replace a RecordDecl 
with another one, it's easier to replace the one RecordDecl in the Type, 
instead of tracking down and replacing all RecordDecls (forward 
declarations and definition).


-Argiris