Fix add_identifier timing: register each declarator immediately after its declarator via helper rules

Co-authored-by: michael-schwarz <13812333+michael-schwarz@users.noreply.github.com>

Author: Copilot

src/frontc/cparser.mly

@@ -123,15 +123,8 @@ let doDeclaration (loc: cabsloc) (specs: spec_elem list) (nl: init_name list) :
     if nl = [] then
       ONLYTYPEDEF (specs, loc)
     else begin
-      (* Tell the lexer about the new variable names.
-         For initialized declarations, add_identifier was already called in
-         declarator_init_start before the initializer was parsed (C11 6.2.1.7).
-         Only register names that have no initializer here. *)
-      List.iter (fun ((n, _, _, _), init) ->
-        match init with
-        | NO_INIT -> !Lexerhack.add_identifier n
-        | _ -> ()
-      ) nl;
+      (* add_identifier is called in declarator_no_init / declarator_init_start as each
+         declarator is parsed (C11 6.2.1.7), so nothing to do here. *)
       DECDEF ((specs, nl), loc)
     end
 
@@ -395,7 +388,7 @@ let transformOffsetOf (speclist, dtype) member =
 
 %type <Cabs.init_name> init_declarator
 %type <Cabs.init_name list> init_declarator_list
-%type <Cabs.name> declarator declarator_init_start
+%type <Cabs.name> declarator declarator_no_init declarator_init_start
 %type <Cabs.name * expression option> field_decl
 %type <(Cabs.name * expression option) list> field_decl_list
 %type <string * Cabs.decl_type> direct_decl
@@ -1043,14 +1036,23 @@ init_declarator_attr:
 
 ;
 init_declarator:                             /* ISO 6.7 */
-    declarator                          { ($1, NO_INIT) }
+    declarator_no_init                  { ($1, NO_INIT) }
 |   declarator_init_start init_expression location
                                         { let (n, d, a, l) = $1 in ((n, d, a, joinLoc l $3), $2) }
 ;
 
+/* (* Parses "declarator" (without initializer) and immediately adds the declared name as a
+      variable identifier in the lexer hack, so that subsequent declarators in the same
+      declaration see the name as an identifier, not as a type
+      (C11 6.2.1.7: scope begins just after the completion of the declarator). *) */
+declarator_no_init:
+    declarator                          { let (n, _, _, _) = $1 in !Lexerhack.add_identifier n; $1 }
+;
+
 /* (* Parses "declarator =" and adds the declared name as a variable identifier
       in the lexer hack, so that in the initializer the name shadows any typedef
-      with the same name (C11 6.2.1.7: scope begins after completion of declarator). *) */
+      with the same name (C11 6.2.1.7: scope begins just after the completion of the
+      declarator). *) */
 declarator_init_start:
     declarator EQ                       { let (n, _, _, _) = $1 in !Lexerhack.add_identifier n; $1 }
 ;