Line data    Source code

       1              : // Copyright (C) 2026 Free Software Foundation, Inc.
       2              : 
       3              : // This file is part of GCC.
       4              : 
       5              : // GCC is free software; you can redistribute it and/or modify it under
       6              : // the terms of the GNU General Public License as published by the Free
       7              : // Software Foundation; either version 3, or (at your option) any later
       8              : // version.
       9              : 
      10              : // GCC is distributed in the hope that it will be useful, but WITHOUT ANY
      11              : // WARRANTY; without even the implied warranty of MERCHANTABILITY or
      12              : // FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
      13              : // for more details.
      14              : 
      15              : // You should have received a copy of the GNU General Public License
      16              : // along with GCC; see the file COPYING3.  If not see
      17              : // <http://www.gnu.org/licenses/>.
      18              : 
      19              : #include "rust-feature-collector.h"
      20              : #include "rust-attribute-values.h"
      21              : 
      22              : namespace Rust {
      23              : namespace Features {
      24              : 
      25         4522 : FeatureCollector::FeatureCollector () : features (CrateFeatures{UNKNOWN_NODEID})
      26         4522 : {}
      27              : 
      28              : CrateFeatures
      29         4522 : FeatureCollector::collect (AST::Crate &crate)
      30              : {
      31         4522 :   features.valid_lang_features.clear ();
      32         4522 :   features.valid_lib_features.clear ();
      33         4522 :   features.crate_id = crate.get_node_id ();
      34              : 
      35         4522 :   visit (crate);
      36              : 
      37         4522 :   return features;
      38              : }
      39              : 
      40              : namespace {
      41              : bool
      42        11256 : is_feature_attribute (const AST::Attribute &attribute)
      43              : {
      44        11256 :   return Values::Attributes::FEATURE == attribute.get_path ().as_string ();
      45              : }
      46              : 
      47              : // check for empty feature, such as `#![feature], this is an error
      48              : bool
      49         6604 : is_valid_feature_attribute (const AST::Attribute &attribute)
      50              : {
      51         6604 :   return !attribute.empty_input ();
      52              : }
      53              : } // namespace
      54              : 
      55              : void
      56         6602 : FeatureCollector::add_features_from_token_tree (
      57              :   const AST::DelimTokenTree &delim_ttree)
      58              : {
      59         6602 :   std::unique_ptr<AST::AttrInputMetaItemContainer> meta_item (
      60         6602 :     delim_ttree.parse_to_meta_item ());
      61         6602 :   add_features_from_meta_item_container (*meta_item);
      62         6602 : }
      63              : 
      64              : void
      65         6603 : FeatureCollector::add_features_from_meta_item_container (
      66              :   const AST::AttrInputMetaItemContainer &meta_item_container)
      67              : {
      68        13377 :   for (const auto &item : meta_item_container.get_items ())
      69              :     {
      70         6774 :       const auto &name_str = item->as_string ();
      71              : 
      72              :       // TODO: detect duplicates
      73         6774 :       if (auto tname = Feature::as_name (name_str))
      74         6769 :         features.valid_lang_features.insert (*tname);
      75              :       else
      76            5 :         features.valid_lib_features.emplace (name_str, item->get_locus ());
      77         6774 :     }
      78         6603 : }
      79              : 
      80              : void
      81        11256 : FeatureCollector::identify_feature (const AST::Attribute &attribute)
      82              : {
      83        11256 :   if (is_feature_attribute (attribute))
      84              :     {
      85         6604 :       if (!is_valid_feature_attribute (attribute))
      86              :         {
      87            1 :           rust_error_at (attribute.get_locus (), ErrorCode::E0556,
      88              :                          "malformed %<feature%> attribute input");
      89            1 :           return;
      90              :         }
      91         6603 :       const auto &attr_input = attribute.get_attr_input ();
      92         6603 :       auto type = attr_input.get_attr_input_type ();
      93         6603 :       if (type == AST::AttrInput::AttrInputType::TOKEN_TREE)
      94              :         {
      95         6602 :           const auto &delim_ttree = static_cast<const AST::DelimTokenTree &> (
      96         6602 :             attribute.get_attr_input ());
      97         6602 :           add_features_from_token_tree (delim_ttree);
      98              :         }
      99            1 :       else if (type == AST::AttrInput::AttrInputType::META_ITEM)
     100              :         {
     101              :           // We can find a meta item in #[cfg(toto),feature(xxxx)]
     102            1 :           const auto &meta_item_container
     103              :             = static_cast<const AST::AttrInputMetaItemContainer &> (attr_input);
     104            1 :           add_features_from_meta_item_container (meta_item_container);
     105              :         }
     106              :     }
     107              : }
     108              : 
     109              : void
     110         4522 : FeatureCollector::visit (AST::Crate &crate)
     111              : {
     112        15778 :   for (const auto &attribute : crate.inner_attrs)
     113        11256 :     identify_feature (attribute);
     114         4522 : }
     115              : 
     116              : } // namespace Features
     117              : } // namespace Rust