From patchwork Tue Nov 30 14:13:26 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jakub Jelinek X-Patchwork-Id: 48286 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id F15CC3857835 for ; Tue, 30 Nov 2021 14:14:49 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org F15CC3857835 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1638281690; bh=U0+2uafoNzGgurvDcwY04URvsl5eF9uiNoWexl7lus8=; h=Date:To:Subject:References:In-Reply-To:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=TFnTMiLCshFtnXSndqdZglmqyv9ejrpnr4KNzKhLbtS/F1FU8CuNSpRqsuwDdJ79C 1ezMjbf48x5RHmtBqDnvtcy5b+SS8HQtO6+eZbj8xTBvD6JkWjcyHSgE92yoJFDj8G 1F7MQ9yuLc8NDwO9Lsg74GLviKPQifH/yC/OVNo4= X-Original-To: gcc-patches@gcc.gnu.org Delivered-To: gcc-patches@gcc.gnu.org Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by sourceware.org (Postfix) with ESMTPS id C30DA385BF92 for ; Tue, 30 Nov 2021 14:13:37 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org C30DA385BF92 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-124-OG3ppjiWNGesWPC_80z7OQ-1; Tue, 30 Nov 2021 09:13:36 -0500 X-MC-Unique: OG3ppjiWNGesWPC_80z7OQ-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 6EBC6874981 for ; Tue, 30 Nov 2021 14:13:35 +0000 (UTC) Received: from tucnak.zalov.cz (unknown [10.39.194.188]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 1AC9119724; Tue, 30 Nov 2021 14:13:29 +0000 (UTC) Received: from tucnak.zalov.cz (localhost [127.0.0.1]) by tucnak.zalov.cz (8.16.1/8.16.1) with ESMTPS id 1AUEDQ5u2949741 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Tue, 30 Nov 2021 15:13:27 +0100 Received: (from jakub@localhost) by tucnak.zalov.cz (8.16.1/8.16.1/Submit) id 1AUEDQ3U2949740; Tue, 30 Nov 2021 15:13:26 +0100 Date: Tue, 30 Nov 2021 15:13:26 +0100 To: Jason Merrill Subject: [PATCH] libcpp, v2: Fix up #__VA_OPT__ handling [PR103415] Message-ID: <20211130141326.GO2646553@tucnak> References: <20211126093300.GF2646553@tucnak> MIME-Version: 1.0 In-Reply-To: X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Disposition: inline X-Spam-Status: No, score=-5.6 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Jakub Jelinek via Gcc-patches From: Jakub Jelinek Reply-To: Jakub Jelinek Cc: gcc-patches@gcc.gnu.org Errors-To: gcc-patches-bounces+patchwork=sourceware.org@gcc.gnu.org Sender: "Gcc-patches" On Mon, Nov 29, 2021 at 07:28:10PM -0500, Jason Merrill wrote: > Please add some of this explanation to the "paste any tokens" comment in the > code. Ok. > > + while (rhs->flags & PASTE_LEFT); > > + if ((flags & PREV_WHITE) > > + && (token->flags & PREV_WHITE) == 0) > > + const_cast(token)->flags > > + |= PREV_WHITE; > > Hmm, shouldn't paste_tokens handle copying PREV_WHITE? Copying there PREV_FALLTHROUGH fixes the new Wimplicit-fallthrough-38.c testcase, I couldn't find where doing the copying of PREV_WHITE would make an observable difference outside of __VA_OPT__, e.g. #define F(x) #x #define G(x) F(x) #define H G({a##b) #define I G({ a##b) const char *h = H; const char *i = I; results in "{ab" and "{ ab" before/after the patch. But copying it in paste_tokens looks cleaner... 2021-11-30 Jakub Jelinek PR preprocessor/103415 libcpp/ * macro.c (stringify_arg): Remove va_opt argument and va_opt handling. (paste_tokens): On successful paste or in PREV_WHITE and PREV_FALLTHROUGH flags from the *plhs token to the new token. (replace_args): Adjust stringify_arg callers. For #__VA_OPT__, perform token pasting in a separate loop before stringify_arg call. gcc/testsuite/ * c-c++-common/cpp/va-opt-8.c: New test. * c-c++-common/Wimplicit-fallthrough-38.c: New test. Jakub --- libcpp/macro.c.jj 2021-11-26 10:09:50.278020239 +0100 +++ libcpp/macro.c 2021-11-30 14:05:25.274132482 +0100 @@ -295,7 +295,7 @@ static cpp_context *next_context (cpp_re static const cpp_token *padding_token (cpp_reader *, const cpp_token *); static const cpp_token *new_string_token (cpp_reader *, uchar *, unsigned int); static const cpp_token *stringify_arg (cpp_reader *, const cpp_token **, - unsigned int, bool); + unsigned int); static void paste_all_tokens (cpp_reader *, const cpp_token *); static bool paste_tokens (cpp_reader *, location_t, const cpp_token **, const cpp_token *); @@ -834,8 +834,7 @@ cpp_quote_string (uchar *dest, const uch /* Convert a token sequence FIRST to FIRST+COUNT-1 to a single string token according to the rules of the ISO C #-operator. */ static const cpp_token * -stringify_arg (cpp_reader *pfile, const cpp_token **first, unsigned int count, - bool va_opt) +stringify_arg (cpp_reader *pfile, const cpp_token **first, unsigned int count) { unsigned char *dest; unsigned int i, escape_it, backslash_count = 0; @@ -852,24 +851,6 @@ stringify_arg (cpp_reader *pfile, const { const cpp_token *token = first[i]; - if (va_opt && (token->flags & PASTE_LEFT)) - { - location_t virt_loc = pfile->invocation_location; - const cpp_token *rhs; - do - { - if (i == count) - abort (); - rhs = first[++i]; - if (!paste_tokens (pfile, virt_loc, &token, rhs)) - { - --i; - break; - } - } - while (rhs->flags & PASTE_LEFT); - } - if (token->type == CPP_PADDING) { if (source == NULL @@ -1003,6 +984,7 @@ paste_tokens (cpp_reader *pfile, locatio return false; } + lhs->flags |= (*plhs)->flags & (PREV_WHITE | PREV_FALLTHROUGH); *plhs = lhs; _cpp_pop_buffer (pfile); return true; @@ -1945,8 +1927,7 @@ replace_args (cpp_reader *pfile, cpp_has if (src->flags & STRINGIFY_ARG) { if (!arg->stringified) - arg->stringified = stringify_arg (pfile, arg->first, arg->count, - false); + arg->stringified = stringify_arg (pfile, arg->first, arg->count); } else if ((src->flags & PASTE_LEFT) || (src != macro->exp.tokens && (src[-1].flags & PASTE_LEFT))) @@ -2066,11 +2047,46 @@ replace_args (cpp_reader *pfile, cpp_has { unsigned int count = start ? paste_flag - start : tokens_buff_count (buff); - const cpp_token *t - = stringify_arg (pfile, - start ? start + 1 - : (const cpp_token **) (buff->base), - count, true); + const cpp_token **first + = start ? start + 1 + : (const cpp_token **) (buff->base); + unsigned int i, j; + + /* Paste any tokens that need to be pasted before calling + stringify_arg, because stringify_arg uses pfile->u_buff + which paste_tokens can use as well. */ + for (i = 0, j = 0; i < count; i++, j++) + { + const cpp_token *token = first[i]; + + if (token->flags & PASTE_LEFT) + { + location_t virt_loc = pfile->invocation_location; + const cpp_token *rhs; + do + { + if (i == count) + abort (); + rhs = first[++i]; + if (!paste_tokens (pfile, virt_loc, &token, rhs)) + { + --i; + break; + } + } + while (rhs->flags & PASTE_LEFT); + } + + first[j] = token; + } + if (j != i) + { + while (i-- != j) + tokens_buff_remove_last_token (buff); + count = j; + } + + const cpp_token *t = stringify_arg (pfile, first, count); while (count--) tokens_buff_remove_last_token (buff); if (src->flags & PASTE_LEFT) --- gcc/testsuite/c-c++-common/cpp/va-opt-8.c.jj 2021-11-30 13:59:28.277305079 +0100 +++ gcc/testsuite/c-c++-common/cpp/va-opt-8.c 2021-11-30 13:59:28.277305079 +0100 @@ -0,0 +1,18 @@ +/* PR preprocessor/103415 */ +/* { dg-do run } */ +/* { dg-options "-std=gnu99" { target c } } */ +/* { dg-options "-std=c++20" { target c++ } } */ + +#define n(x, ...) = #__VA_OPT__(x##3) +#define o(x, ...) #__VA_OPT__(x##__VA_ARGS__##9) +const char *c n(1 2, 4); +const char *d = o(5 6, 7 8); + +int +main () +{ + if (__builtin_strcmp (c, "1 23") + || __builtin_strcmp (d, "5 67 89")) + __builtin_abort (); + return 0; +} --- gcc/testsuite/c-c++-common/Wimplicit-fallthrough-38.c.jj 2021-11-30 14:10:16.309915336 +0100 +++ gcc/testsuite/c-c++-common/Wimplicit-fallthrough-38.c 2021-11-30 14:10:33.708663223 +0100 @@ -0,0 +1,24 @@ +/* { dg-do compile } */ +/* { dg-options "-Wimplicit-fallthrough=3" } */ + +#define FOO \ +int \ +foo (int a) \ +{ \ + switch (a) \ + { \ + case 1: \ + ++a; \ + /* FALLTHRU */ \ + case 2: \ + ++a; \ + /* FALLTHRU */ \ + ca##se 3: \ + ++a; \ + default: \ + break; \ + } \ + return a; \ +} + +FOO