From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-00641c01.pphosted.com (mx0a-00641c01.pphosted.com [205.220.165.146]) by sourceware.org (Postfix) with ESMTPS id B7E7F3857C4D; Thu, 7 Dec 2023 05:39:54 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org B7E7F3857C4D Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=gcc.gnu.org Authentication-Results: sourceware.org; spf=fail smtp.mailfrom=gcc.gnu.org ARC-Filter: OpenARC Filter v1.0.0 sourceware.org B7E7F3857C4D Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=205.220.165.146 ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1701927596; cv=none; b=LNUFwVmBTadxIcWJ1v2fwcyhwMfYn1SSVhcBbSDyKbSdK5MsQ4IIrcqYOws1qsTVUw5Y8U5RZroON5zRA6W7gUdXgoOhKK/a8L1KrnK4QfQrPh8A56hEPMElKD+9v4OpxAFmWCDuMoMNi444Tt0+1MQ2jX+cOZAYGo2LDppfjfk= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1701927596; c=relaxed/simple; bh=Z2OBwP9PyfmVefR1khkSQmNCIgpRgRPLjggF0OtwFx8=; h=From:To:Subject:Date:Message-ID:MIME-Version; b=ZkKRm8RrvmjNf4l+EfAEu5DQ3KmwcTlOolL7UvnyyIFL5lkd4ge7dvslpunbKhMUjLryoS2BS1fDMzInk0YfacSl0QYTQzxON2rx6QpQRSIIsElBQ5rMlpM4gDp9+Ko4LOgl64QXRb/+iyLEhNvlbXxM96Pz75rD9pMoM8H9wwQ= ARC-Authentication-Results: i=1; server2.sourceware.org Received: from pps.filterd (m0247474.ppops.net [127.0.0.1]) by mx0a-00641c01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 3B75SCkk005261; Thu, 7 Dec 2023 05:39:53 GMT Received: from mxout26.s.uw.edu (mxout26.s.uw.edu [140.142.234.176]) by mx0a-00641c01.pphosted.com (PPS) with ESMTPS id 3uu3dmhry6-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 07 Dec 2023 05:39:53 +0000 Received: from smtp.washington.edu (smtp.washington.edu [128.208.60.54]) by mxout26.s.uw.edu (8.14.4+UW20.07/8.14.4+UW22.04) with ESMTP id 3B75dU1Z005183 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 6 Dec 2023 21:39:30 -0800 X-Auth-Received: from kmatsui-ThinkPad-X1-Carbon-Gen-9.dhcp4.washington.edu ([10.154.75.142]) (authenticated authid=kmatsui) by smtp.washington.edu (8.16.1+UW21.10/8.14.4+UW19.10) with ESMTPSA id 3B75adQ4020981 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 6 Dec 2023 21:39:30 -0800 X-UW-Orig-Sender: kmatsui@smtp.washington.edu From: Ken Matsui To: gcc-patches@gcc.gnu.org Cc: libstdc++@gcc.gnu.org, Ken Matsui Subject: [PATCH v26 03/23] c++: Accept the use of built-in trait identifiers Date: Wed, 6 Dec 2023 21:32:58 -0800 Message-ID: <20231207053633.1001720-4-kmatsui@gcc.gnu.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231207053633.1001720-1-kmatsui@gcc.gnu.org> References: <20231024020424.699427-1-kmatsui@gcc.gnu.org> <20231207053633.1001720-1-kmatsui@gcc.gnu.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Proofpoint-GUID: 5PTnKZTEe6n-m3K2g3vmHYn9p0tUS6_k X-Proofpoint-ORIG-GUID: 5PTnKZTEe6n-m3K2g3vmHYn9p0tUS6_k X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.997,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-12-06_20,2023-12-06_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 impostorscore=0 bulkscore=0 spamscore=0 mlxlogscore=999 malwarescore=0 adultscore=0 clxscore=1034 suspectscore=0 priorityscore=1501 lowpriorityscore=0 phishscore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2311290000 definitions=main-2312070000 X-Spam-Status: No, score=-13.2 required=5.0 tests=BAYES_00,GIT_PATCH_0,JMQ_SPF_NEUTRAL,KAM_DMARC_STATUS,RCVD_IN_DNSWL_LOW,RCVD_IN_MSPIKE_H4,RCVD_IN_MSPIKE_WL,SPF_HELO_NONE,SPF_NEUTRAL,TXREP,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: This patch accepts the use of built-in trait identifiers when they are actually not used as traits. Specifically, we check if the subsequent token is '(' for ordinary built-in traits or is '<' only for the special __type_pack_element built-in trait. If those identifiers are used differently, the parser treats them as normal identifiers. This allows us to accept code like: struct __is_pointer {};. gcc/cp/ChangeLog: * parser.cc (cp_lexer_lookup_trait): Rename to ... (cp_lexer_peek_trait): ... this. Handle a subsequent token for the corresponding built-in trait. (cp_lexer_lookup_trait_expr): Rename to ... (cp_lexer_peek_trait_expr): ... this. (cp_lexer_lookup_trait_type): Rename to ... (cp_lexer_peek_trait_type): ... this. (cp_lexer_next_token_is_decl_specifier_keyword): Call cp_lexer_peek_trait_type. (cp_parser_simple_type_specifier): Likewise. (cp_parser_primary_expression): Call cp_lexer_peek_trait_expr. Signed-off-by: Ken Matsui --- gcc/cp/parser.cc | 53 +++++++++++++++++++++++++++++++----------------- 1 file changed, 34 insertions(+), 19 deletions(-) diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc index a416b58a2a5..bf5add5cae9 100644 --- a/gcc/cp/parser.cc +++ b/gcc/cp/parser.cc @@ -246,12 +246,12 @@ static void cp_lexer_start_debugging (cp_lexer *) ATTRIBUTE_UNUSED; static void cp_lexer_stop_debugging (cp_lexer *) ATTRIBUTE_UNUSED; -static const cp_trait *cp_lexer_lookup_trait - (const cp_token *); -static const cp_trait *cp_lexer_lookup_trait_expr - (const cp_token *); -static const cp_trait *cp_lexer_lookup_trait_type - (const cp_token *); +static const cp_trait *cp_lexer_peek_trait + (cp_lexer *); +static const cp_trait *cp_lexer_peek_trait_expr + (cp_lexer *); +static const cp_trait *cp_lexer_peek_trait_type + (cp_lexer *); static cp_token_cache *cp_token_cache_new (cp_token *, cp_token *); @@ -1188,15 +1188,29 @@ cp_keyword_starts_decl_specifier_p (enum rid keyword) } } -/* Look ups the corresponding built-in trait if a given token is - a built-in trait. Otherwise, returns nullptr. */ +/* Peeks the corresponding built-in trait if the first token is + a built-in trait and the second token is either `(' or `<' depending + on the trait. Otherwise, returns nullptr. */ static const cp_trait * -cp_lexer_lookup_trait (const cp_token *token) +cp_lexer_peek_trait (cp_lexer *lexer) { - if (token->type == CPP_NAME && IDENTIFIER_TRAIT_P (token->u.value)) - return &cp_traits[IDENTIFIER_CP_INDEX (token->u.value)]; + const cp_token *token1 = cp_lexer_peek_token (lexer); + if (token1->type == CPP_NAME && IDENTIFIER_TRAIT_P (token1->u.value)) + { + const cp_trait &trait = cp_traits[IDENTIFIER_CP_INDEX (token1->u.value)]; + const bool is_pack_element = (trait.kind == CPTK_TYPE_PACK_ELEMENT); + + /* Check if the subsequent token is a `<' token to + __type_pack_element or is a `(' token to everything else. */ + const cp_token *token2 = cp_lexer_peek_nth_token (lexer, 2); + if (is_pack_element && token2->type != CPP_LESS) + return nullptr; + if (!is_pack_element && token2->type != CPP_OPEN_PAREN) + return nullptr; + return &trait; + } return nullptr; } @@ -1204,9 +1218,9 @@ cp_lexer_lookup_trait (const cp_token *token) built-in trait. */ static const cp_trait * -cp_lexer_lookup_trait_expr (const cp_token *token) +cp_lexer_peek_trait_expr (cp_lexer *lexer) { - const cp_trait *trait = cp_lexer_lookup_trait (token); + const cp_trait *trait = cp_lexer_peek_trait (lexer); if (trait && !trait->type) return trait; @@ -1217,9 +1231,9 @@ cp_lexer_lookup_trait_expr (const cp_token *token) built-in trait. */ static const cp_trait * -cp_lexer_lookup_trait_type (const cp_token *token) +cp_lexer_peek_trait_type (cp_lexer *lexer) { - const cp_trait *trait = cp_lexer_lookup_trait (token); + const cp_trait *trait = cp_lexer_peek_trait (lexer); if (trait && trait->type) return trait; @@ -1233,9 +1247,10 @@ cp_lexer_next_token_is_decl_specifier_keyword (cp_lexer *lexer) { cp_token *token; - token = cp_lexer_peek_token (lexer); - if (cp_lexer_lookup_trait_type (token)) + if (cp_lexer_peek_trait_type (lexer)) return true; + + token = cp_lexer_peek_token (lexer); return cp_keyword_starts_decl_specifier_p (token->keyword); } @@ -6133,7 +6148,7 @@ cp_parser_primary_expression (cp_parser *parser, `::' as the beginning of a qualified-id, or the "operator" keyword. */ case CPP_NAME: - if (const cp_trait* trait = cp_lexer_lookup_trait_expr (token)) + if (const cp_trait* trait = cp_lexer_peek_trait_expr (parser->lexer)) return cp_parser_trait (parser, trait); /* FALLTHRU */ case CPP_SCOPE: @@ -20151,7 +20166,7 @@ cp_parser_simple_type_specifier (cp_parser* parser, } /* If token is a type-yielding built-in traits, parse it. */ - const cp_trait* trait = cp_lexer_lookup_trait_type (token); + const cp_trait* trait = cp_lexer_peek_trait_type (parser->lexer); if (trait) { type = cp_parser_trait (parser, trait); -- 2.43.0