From 45531c73d9f28a2430b98958b45c4aab85f66261 Mon Sep 17 00:00:00 2001
From: David Malcolm <dmalcolm@redhat.com>
Date: Thu, 2 Oct 2025 11:49:50 -0400
Subject: [PATCH 27/30] FIXME: C++ AST

---
 gcc/cp/name-lookup.cc |  1 +
 gcc/cp/parser.cc      | 57 +++++++++++++++++++++++++++++++++++++++++++
 gcc/cp/parser.h       |  5 ++++
 3 files changed, 63 insertions(+)

diff --git a/gcc/cp/name-lookup.cc b/gcc/cp/name-lookup.cc
index b7fc43391cf..cbaedea9413 100644
--- a/gcc/cp/name-lookup.cc
+++ b/gcc/cp/name-lookup.cc
@@ -18,6 +18,7 @@ You should have received a copy of the GNU General Public License
 along with GCC; see the file COPYING3.  If not see
 <http://www.gnu.org/licenses/>.  */
 
+#define INCLUDE_LIST
 #include "config.h"
 #include "system.h"
 #include "coretypes.h"
diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
index 53fbb75b15a..cb1ce9276f6 100644
--- a/gcc/cp/parser.cc
+++ b/gcc/cp/parser.cc
@@ -20,7 +20,9 @@ along with GCC; see the file COPYING3.  If not see
 
 #include "config.h"
 #include "omp-selectors.h"
+#define INCLUDE_LIST
 #define INCLUDE_STRING
+#define INCLUDE_VECTOR
 #include "system.h"
 #include "coretypes.h"
 #include "cp-tree.h"
@@ -51,6 +53,8 @@ along with GCC; see the file COPYING3.  If not see
 #include "builtins.h"
 #include "contracts.h"
 #include "analyzer/analyzer-language.h"
+#include "channels.h"
+#include "topics/ast-events.h"
 
 
 /* The lexer.  */
@@ -4791,6 +4795,9 @@ cp_parser_new (cp_lexer *lexer)
   /* We haven't yet seen an 'extern "C"'.  */
   parser->innermost_linkage_specification_location = UNKNOWN_LOCATION;
 
+  parser->ast_events_channel
+    = g->get_channels ().ast_events_channel.get_if_active ();
+
   return parser;
 }
 
@@ -5482,6 +5489,48 @@ finish_userdef_string_literal (tree literal)
   return error_mark_node;
 }
 
+class auto_notify_ast_node
+{
+public:
+  auto_notify_ast_node (cp_parser *parser, const char *kind)
+  : m_parser (parser),
+    m_kind (kind)
+  {
+    // FIXME: unlikely
+    // gengtype doesn't understand  [[unlikely]] , and is it legal
+    // in c++14 anyway?
+    if (parser->ast_events_channel)
+      parser->ast_events_channel->publish
+	(gcc::topics::ast_events::begin_node {kind, get_next_loc ()});
+  }
+
+  ~auto_notify_ast_node ()
+  {
+    // FIXME: unlikely
+    if (m_parser->ast_events_channel)
+      m_parser->ast_events_channel->publish
+	(gcc::topics::ast_events::end_node {m_kind, get_prev_loc ()});
+  }
+
+  location_t
+  get_next_loc () const
+  {
+    return cp_lexer_peek_token (m_parser->lexer)->location;
+  }
+
+  location_t
+  get_prev_loc () const
+  {
+    if (const cp_token *tok = cp_lexer_safe_previous_token (m_parser->lexer))
+      return tok->location;
+    return UNKNOWN_LOCATION;
+  }
+
+private:
+  cp_parser *const m_parser;
+  const char *const m_kind;
+};
+
 
 /* Basic concepts [gram.basic]  */
 
@@ -5515,6 +5564,10 @@ cp_parser_translation_unit (cp_parser* parser)
   bool implicit_extern_c = false;
 
   /* Parse until EOF.  */
+  // FIXME
+  {
+  auto_notify_ast_node sentinel (parser, "translation-unit");
+
   for (;;)
     {
       cp_token *token = cp_lexer_peek_token (parser->lexer);
@@ -5611,6 +5664,7 @@ cp_parser_translation_unit (cp_parser* parser)
 				     false, true);
       parser->omp_begin_declare_variant_map = NULL;
     }
+  }
 
 #if ENABLE_ANALYZER
   if (flag_analyzer)
@@ -22280,6 +22334,8 @@ cp_parser_type_specifier (cp_parser* parser,
 			  int* declares_class_or_enum,
 			  bool* is_cv_qualifier)
 {
+  auto_notify_ast_node sentinel (parser, "type-specifier");
+
   tree type_spec = NULL_TREE;
   cp_token *token;
   enum rid keyword;
@@ -23747,6 +23803,7 @@ cp_parser_elaborated_type_specifier (cp_parser* parser,
 static tree
 cp_parser_enum_specifier (cp_parser* parser)
 {
+  auto_notify_ast_node sentinel (parser, "enum-specifier");
   tree identifier;
   tree type = NULL_TREE;
   tree prev_scope;
diff --git a/gcc/cp/parser.h b/gcc/cp/parser.h
index ddef98d900a..046ae03dc64 100644
--- a/gcc/cp/parser.h
+++ b/gcc/cp/parser.h
@@ -23,6 +23,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "tree.h"
 #include "cp/cp-tree.h"
 #include "c-family/c-pragma.h"
+#include "topics/ast-events.h"
 
 /* A token's value and its associated deferred access checks and
    qualifying scope.  */
@@ -470,6 +471,10 @@ struct GTY(()) cp_parser {
      constructs that still need to be registered with their base functions.  */
   vec<omp_begin_declare_variant_map_entry, va_gc> *
     omp_begin_declare_variant_map;
+
+  // FIXME
+  const pub_sub::channel<gcc::topics::ast_events::subscriber> * GTY((skip))
+    ast_events_channel;
 };
 
 /* In parser.cc  */
-- 
2.49.0