From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by sourceware.org (Postfix) with ESMTPS id CE5C2386F452 for ; Fri, 17 Dec 2021 00:52:58 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org CE5C2386F452 Received: from mail-qk1-f198.google.com (mail-qk1-f198.google.com [209.85.222.198]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-263-2Qo0rJBCOKGkjZftDKW2vg-1; Thu, 16 Dec 2021 19:52:57 -0500 X-MC-Unique: 2Qo0rJBCOKGkjZftDKW2vg-1 Received: by mail-qk1-f198.google.com with SMTP id a10-20020a05620a066a00b0046742e40049so387554qkh.14 for ; Thu, 16 Dec 2021 16:52:57 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=DVh7vjeBJsPpGJDgqMl6D+cx1E2MNdpE2KObFy6uw+U=; b=K5mVT4dII66+lnfOqGZ5SVOK/gCksMXadobmmv2vhMNNI6mXZBv4X75Nk7R2ZQEFrj YWJYMG7vXClEqn6Xnnr5sd/Abdz5pa2Un9WVYaN8bQEBtcJ9/Tlsptdm2cAdJU4bM+bW Pk2sN3BcJr+FeJlvyZ51JcKUgoai42iTsEezq+4pcK3POVyLWDBL/Mx4WN1Vhi0hTd8F ykvFqcnIkUwyIU+O9eTfEmFXMwG3SaS9kySwZG6pVB4fi3APoWo2vUGNlpwr0KpsuDC1 7E9HVeVZh+TyL4I4Ofk/XgUpRkwzL2kybToOCZiaCJ8TQKAckwNSYKs/spnt+awN483y aeRw== X-Gm-Message-State: AOAM532Hy5qSwjPuDqGPp98vznEnmirNMErhDyqSKmtHBGIb+nkoH/yb 26r+UYC326G3092Hb9sSbxVOCOLYRZMnpSDTYbBF2OUrm6QztS+BukO8lCimNy0dBX4ElCybKJd pqWu58+sEydCz+Gl1rQ== X-Received: by 2002:a05:620a:2552:: with SMTP id s18mr407774qko.223.1639702376728; Thu, 16 Dec 2021 16:52:56 -0800 (PST) X-Google-Smtp-Source: ABdhPJwnom36IGiuy3IdOcuR9rHxkduB6ggQxF7ydeQ6apzpQCDLY3YdtuKCNsnRZuvFWVzBfwbuvQ== X-Received: by 2002:a05:620a:2552:: with SMTP id s18mr407768qko.223.1639702376368; Thu, 16 Dec 2021 16:52:56 -0800 (PST) Received: from redhat.com ([2601:184:4780:4310::aac2]) by smtp.gmail.com with ESMTPSA id l25sm3777363qkk.48.2021.12.16.16.52.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 16 Dec 2021 16:52:55 -0800 (PST) Date: Thu, 16 Dec 2021 19:52:53 -0500 From: Marek Polacek To: Jakub Jelinek Cc: GCC Patches , Jason Merrill , Joseph Myers Subject: [PATCH v2] attribs: Fix wrong error with -Wno-attribute=A::b [PR103649] Message-ID: References: <20211216223555.820800-1-polacek@redhat.com> <20211216225346.GA2646553@tucnak> MIME-Version: 1.0 In-Reply-To: <20211216225346.GA2646553@tucnak> User-Agent: Mutt/2.1.3 (2021-09-10) X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Spam-Status: No, score=-13.2 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL, 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-List-Received-Date: Fri, 17 Dec 2021 00:53:00 -0000 On Thu, Dec 16, 2021 at 11:53:46PM +0100, Jakub Jelinek wrote: > On Thu, Dec 16, 2021 at 05:35:55PM -0500, Marek Polacek wrote: > > My patch to implement -Wno-attribute=A::b caused a bogus error when > > parsing > > > > [[foo::bar(1, 2)]]; > > > > when -Wno-attributes=foo::bar was specified on the command line, because > > when we create a fake foo::bar attribute and insert it into our attribute > > table, it is created with max_length == 0 which doesn't allow any args. > > That is wrong -- we know nothing about the attribute, so we shouldn't > > require any specific number of arguments. > > > > Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk? > > > > PR c/103649 > > > > gcc/ChangeLog: > > > > * attribs.c (handle_ignored_attributes_option): Create the fake > > attribute with max_length == -1. > > > > gcc/testsuite/ChangeLog: > > > > * c-c++-common/Wno-attributes-6.c: New test. > > I'm afraid this still changes behavior. 0, -1 range attribute arguments > are parsed normally, while unknown attributes have the balanced token > sequence skipped. > E.g. the omp::{directive,sequence} attribute arguments are much more complex > than what the normal parsing can handle. > Can you make max -2 instead and special case it in the C and C++ FE > attribute handling and in a testcase try something that is a balanced token > sequence but not really valid when parsed as ordinary attributes' arguments? Ah I see what you mean now. Fixed here, thanks. Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk? -- >8 -- My patch to implement -Wno-attribute=A::b caused a bogus error when parsing [[foo::bar(1, 2)]]; when -Wno-attributes=foo::bar was specified on the command line, because when we create a fake foo::bar attribute and insert it into our attribute table, it is created with max_length == 0 which doesn't allow any args. That is wrong -- we know nothing about the attribute, so we shouldn't require any specific number of arguments. And since unknown attributes can be rather complex (see for example omp::{directive,sequence}), we must skip parsing their arguments. To that end, I'm using max_length with value -2. PR c/103649 gcc/ChangeLog: * attribs.c (handle_ignored_attributes_option): Create the fake attribute with max_length == -2. * tree-core.h (struct attribute_spec): Document that max_length can be -2. gcc/c/ChangeLog: * c-parser.c (c_parser_std_attribute): Skip parsing of the attribute arguments when max_length == -2. gcc/cp/ChangeLog: * parser.c (cp_parser_std_attribute): Skip parsing of the attribute arguments when max_length == -2. gcc/testsuite/ChangeLog: * c-c++-common/Wno-attributes-6.c: New test. --- gcc/attribs.c | 2 +- gcc/c/c-parser.c | 4 +++- gcc/cp/parser.c | 4 +++- gcc/testsuite/c-c++-common/Wno-attributes-6.c | 14 ++++++++++++++ gcc/tree-core.h | 4 +++- 5 files changed, 24 insertions(+), 4 deletions(-) create mode 100644 gcc/testsuite/c-c++-common/Wno-attributes-6.c diff --git a/gcc/attribs.c b/gcc/attribs.c index 29703e75fba..6af7f93e61c 100644 --- a/gcc/attribs.c +++ b/gcc/attribs.c @@ -304,7 +304,7 @@ handle_ignored_attributes_option (vec *v) We can't free it here, so squirrel away the pointers. */ attribute_spec *table = new attribute_spec[2]; ignored_attributes_table.safe_push (table); - table[0] = { attr, 0, 0, false, false, false, false, nullptr, nullptr }; + table[0] = { attr, 0, -2, false, false, false, false, nullptr, nullptr }; table[1] = { nullptr, 0, 0, false, false, false, false, nullptr, nullptr }; register_scoped_attributes (table, IDENTIFIER_POINTER (vendor_id), !attr); diff --git a/gcc/c/c-parser.c b/gcc/c/c-parser.c index d7e5f051ac0..c9068bdbb8a 100644 --- a/gcc/c/c-parser.c +++ b/gcc/c/c-parser.c @@ -4943,7 +4943,9 @@ c_parser_std_attribute (c_parser *parser, bool for_tm) parens.skip_until_found_close (parser); return error_mark_node; } - if (as) + /* When MAX_LENGTH is -2, this is a fake attribute created to + handle -Wno-attributes, and we must skip parsing the arguments. */ + if (as && as->max_length != -2) { bool takes_identifier = (ns != NULL_TREE diff --git a/gcc/cp/parser.c b/gcc/cp/parser.c index 44eed7ea638..763d74eaf6c 100644 --- a/gcc/cp/parser.c +++ b/gcc/cp/parser.c @@ -28979,7 +28979,9 @@ cp_parser_std_attribute (cp_parser *parser, tree attr_ns) /* A GNU attribute that takes an identifier in parameter. */ attr_flag = id_attr; - if (as == NULL) + /* When MAX_LENGTH is -2, this is a fake attribute created to + handle -Wno-attributes, and we must skip parsing the arguments. */ + if (as == NULL || as->max_length == -2) { if ((flag_openmp || flag_openmp_simd) && attr_ns == omp_identifier) { diff --git a/gcc/testsuite/c-c++-common/Wno-attributes-6.c b/gcc/testsuite/c-c++-common/Wno-attributes-6.c new file mode 100644 index 00000000000..0b2dd5aa290 --- /dev/null +++ b/gcc/testsuite/c-c++-common/Wno-attributes-6.c @@ -0,0 +1,14 @@ +/* PR c/103649 */ +/* { dg-do compile { target { c || c++11 } } } */ +/* { dg-additional-options "-Wno-attributes=foo::bar" } */ +/* { dg-additional-options "-Wno-attributes=baz::" } */ +/* { dg-additional-options "-Wno-attributes=womp::womp" } */ +/* { dg-additional-options "-Wno-attributes=qux::foo" } */ + +[[foo::bar(1, 2)]]; /* { dg-warning "attribute ignored" } */ +[[baz::bar(1, 2)]]; /* { dg-warning "attribute ignored" } */ +[[foo::bar(1, 2)]] void f1(); +[[baz::bar(1, 2)]] void f2(); +[[qux::foo({t})]] void f3(); +[[womp::womp (another::directive (threadprivate (t)))]] void f4(); +[[womp::womp (another::directive (threadprivate (t)))]]; /* { dg-warning "attribute ignored" } */ diff --git a/gcc/tree-core.h b/gcc/tree-core.h index 91ae5237d7e..9b37a065d18 100644 --- a/gcc/tree-core.h +++ b/gcc/tree-core.h @@ -2077,7 +2077,9 @@ struct attribute_spec { /* The minimum length of the list of arguments of the attribute. */ int min_length; /* The maximum length of the list of arguments of the attribute - (-1 for no maximum). */ + (-1 for no maximum). It can also be -2 for fake attributes + created for the sake of -Wno-attributes; in that case, we + should skip the balanced token sequence when parsing the attribute. */ int max_length; /* Whether this attribute requires a DECL. If it does, it will be passed from types of DECLs, function return types and array element types to base-commit: 840a22e0fee9e7369a2eb1c9e3c70dcae24a20e4 -- 2.33.1