DCE: Task 4 - Declarations use map → list → merge pattern

analysis/reanalyze/DEADCODE_REFACTOR_PLAN.md

@@ -325,12 +325,15 @@ val is_annotated_* : t -> ... -> bool
 **Pattern**: Same as Task 3 - `builder` (mutable) → `builder list` → `merge_all` → `t` (immutable)
 
 **Changes**:
-- [ ] Create `Declarations` module with `builder` and `t` types
-- [ ] `process_cmt_file` returns `Declarations.builder` (local mutable)
-- [ ] `processCmtFiles` collects into `builder list`
-- [ ] `Declarations.merge_all : builder list -> t`
-- [ ] Solver uses immutable `Declarations.t`
-- [ ] Delete global `DeadCommon.decls`
+- [x] Create `Declarations` module with `builder` and `t` types
+- [x] `process_cmt_file` returns `DceFileProcessing.file_data` containing both `annotations` and `decls` builders
+- [x] `processCmtFiles` collects into `file_data list`
+- [x] `Declarations.merge_all : builder list -> t`
+- [x] Solver uses immutable `Declarations.t`
+- [x] Delete global `DeadCommon.decls`
+- [x] Update `DeadOptionalArgs.forceDelayedItems` to take `~decls:Declarations.t`
+
+**Status**: Complete ✅
 
 **Test**: Process files in different orders - results should be identical.
 

analysis/reanalyze/src/CollectAnnotations.ml

@@ -0,0 +1,149 @@
+(** AST traversal to collect source annotations (@dead, @live, @genType).
+
+    This module traverses the typed AST to find attribute annotations
+    and records them in a FileAnnotations.builder. *)
+
+open DeadCommon
+
+let processAttributes ~state ~config ~doGenType ~name ~pos attributes =
+  let getPayloadFun f = attributes |> Annotation.getAttributePayload f in
+  let getPayload (x : string) =
+    attributes |> Annotation.getAttributePayload (( = ) x)
+  in
+  if
+    doGenType
+    && getPayloadFun Annotation.tagIsOneOfTheGenTypeAnnotations <> None
+  then FileAnnotations.annotate_gentype state pos;
+  if getPayload WriteDeadAnnotations.deadAnnotation <> None then
+    FileAnnotations.annotate_dead state pos;
+  let nameIsInLiveNamesOrPaths () =
+    config.DceConfig.cli.live_names |> List.mem name
+    ||
+    let fname =
+      match Filename.is_relative pos.pos_fname with
+      | true -> pos.pos_fname
+      | false -> Filename.concat (Sys.getcwd ()) pos.pos_fname
+    in
+    let fnameLen = String.length fname in
+    config.DceConfig.cli.live_paths
+    |> List.exists (fun prefix ->
+           String.length prefix <= fnameLen
+           &&
+           try String.sub fname 0 (String.length prefix) = prefix
+           with Invalid_argument _ -> false)
+  in
+  if getPayload liveAnnotation <> None || nameIsInLiveNamesOrPaths () then
+    FileAnnotations.annotate_live state pos;
+  if attributes |> Annotation.isOcamlSuppressDeadWarning then
+    FileAnnotations.annotate_live state pos
+
+let collectExportLocations ~state ~config ~doGenType =
+  let super = Tast_mapper.default in
+  let currentlyDisableWarnings = ref false in
+  let value_binding self
+      ({vb_attributes; vb_pat} as value_binding : Typedtree.value_binding) =
+    (match vb_pat.pat_desc with
+    | Tpat_var (id, {loc = {loc_start = pos}})
+    | Tpat_alias ({pat_desc = Tpat_any}, id, {loc = {loc_start = pos}}) ->
+      if !currentlyDisableWarnings then FileAnnotations.annotate_live state pos;
+      vb_attributes
+      |> processAttributes ~state ~config ~doGenType ~name:(id |> Ident.name)
+           ~pos
+    | _ -> ());
+    super.value_binding self value_binding
+  in
+  let type_kind toplevelAttrs self (typeKind : Typedtree.type_kind) =
+    (match typeKind with
+    | Ttype_record labelDeclarations ->
+      labelDeclarations
+      |> List.iter
+           (fun ({ld_attributes; ld_loc} : Typedtree.label_declaration) ->
+             toplevelAttrs @ ld_attributes
+             |> processAttributes ~state ~config ~doGenType:false ~name:""
+                  ~pos:ld_loc.loc_start)
+    | Ttype_variant constructorDeclarations ->
+      constructorDeclarations
+      |> List.iter
+           (fun
+             ({cd_attributes; cd_loc; cd_args} :
+               Typedtree.constructor_declaration)
+           ->
+             let _process_inline_records =
+               match cd_args with
+               | Cstr_record flds ->
+                 List.iter
+                   (fun ({ld_attributes; ld_loc} : Typedtree.label_declaration)
+                      ->
+                     toplevelAttrs @ cd_attributes @ ld_attributes
+                     |> processAttributes ~state ~config ~doGenType:false
+                          ~name:"" ~pos:ld_loc.loc_start)
+                   flds
+               | Cstr_tuple _ -> ()
+             in
+             toplevelAttrs @ cd_attributes
+             |> processAttributes ~state ~config ~doGenType:false ~name:""
+                  ~pos:cd_loc.loc_start)
+    | _ -> ());
+    super.type_kind self typeKind
+  in
+  let type_declaration self (typeDeclaration : Typedtree.type_declaration) =
+    let attributes = typeDeclaration.typ_attributes in
+    let _ = type_kind attributes self typeDeclaration.typ_kind in
+    typeDeclaration
+  in
+  let value_description self
+      ({val_attributes; val_id; val_val = {val_loc = {loc_start = pos}}} as
+       value_description :
+        Typedtree.value_description) =
+    if !currentlyDisableWarnings then FileAnnotations.annotate_live state pos;
+    val_attributes
+    |> processAttributes ~state ~config ~doGenType ~name:(val_id |> Ident.name)
+         ~pos;
+    super.value_description self value_description
+  in
+  let structure_item self (item : Typedtree.structure_item) =
+    (match item.str_desc with
+    | Tstr_attribute attribute
+      when [attribute] |> Annotation.isOcamlSuppressDeadWarning ->
+      currentlyDisableWarnings := true
+    | _ -> ());
+    super.structure_item self item
+  in
+  let structure self (structure : Typedtree.structure) =
+    let oldDisableWarnings = !currentlyDisableWarnings in
+    super.structure self structure |> ignore;
+    currentlyDisableWarnings := oldDisableWarnings;
+    structure
+  in
+  let signature_item self (item : Typedtree.signature_item) =
+    (match item.sig_desc with
+    | Tsig_attribute attribute
+      when [attribute] |> Annotation.isOcamlSuppressDeadWarning ->
+      currentlyDisableWarnings := true
+    | _ -> ());
+    super.signature_item self item
+  in
+  let signature self (signature : Typedtree.signature) =
+    let oldDisableWarnings = !currentlyDisableWarnings in
+    super.signature self signature |> ignore;
+    currentlyDisableWarnings := oldDisableWarnings;
+    signature
+  in
+  {
+    super with
+    signature;
+    signature_item;
+    structure;
+    structure_item;
+    type_declaration;
+    value_binding;
+    value_description;
+  }
+
+let structure ~state ~config ~doGenType structure =
+  let mapper = collectExportLocations ~state ~config ~doGenType in
+  structure |> mapper.structure mapper |> ignore
+
+let signature ~state ~config signature =
+  let mapper = collectExportLocations ~state ~config ~doGenType:true in
+  signature |> mapper.signature mapper |> ignore

analysis/reanalyze/src/CollectAnnotations.mli

@@ -0,0 +1,18 @@
+(** AST traversal to collect source annotations (@dead, @live, @genType).
+
+    Traverses the typed AST and records annotations in a FileAnnotations.builder. *)
+
+val structure :
+  state:FileAnnotations.builder ->
+  config:DceConfig.t ->
+  doGenType:bool ->
+  Typedtree.structure ->
+  unit
+(** Traverse a structure and collect annotations. *)
+
+val signature :
+  state:FileAnnotations.builder ->
+  config:DceConfig.t ->
+  Typedtree.signature ->
+  unit
+(** Traverse a signature and collect annotations. *)