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 [216.205.24.124]) by sourceware.org (Postfix) with ESMTP id E702F3858D28 for ; Mon, 11 Oct 2021 15:17:16 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org E702F3858D28 Received: from mail-qv1-f72.google.com (mail-qv1-f72.google.com [209.85.219.72]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-221-drS8YeisOf6cVKID3Mb-4Q-1; Mon, 11 Oct 2021 11:17:15 -0400 X-MC-Unique: drS8YeisOf6cVKID3Mb-4Q-1 Received: by mail-qv1-f72.google.com with SMTP id s12-20020ad44b2c000000b00383ab64e632so523219qvw.17 for ; Mon, 11 Oct 2021 08:17:15 -0700 (PDT) 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=SPTpsYd+TdsWZz4RKRCa1GSSqFvRIZBEAgTMXmtZ02Q=; b=JU5c5B2qCPa5wrGpLXRwtkj2pwCW5buLSdO+JhpLt7NGKl5bxHBbJpTT1bkWnTkyM7 UgcKVmjX51MGsXwI4Y6+pcJQFZgfJFI6QgX7aV9lUs8qVaYJ+MrUEUYhiNVvbAxPxRLt k8qbICT51YU+y+73Yr9TtK1oL5nhenScB7EMz5/ZX6yeKWeQo21HC/vNfTyV/HsRqCWV ZxP4qfhmtaEAskh/s2Ret6/3s8G2o+MxA9FuGfxtE5ykKSORu+B/Jq3xGpSo5O1dnwOt XyTFb1C4QEfhoKzKgzl2NE5RyjNh8rjOVNgPt1ipOFfH3Rg/Mf1IhKzYNpQ+oO25BICL mW/g== X-Gm-Message-State: AOAM531NN6T+dsKTwZGfBGc3Op6cYLlHVZZuYpY7jvb+f/vFSw27cLl8 MqcEYkvjwGNXs4xL8U2zvPrP5CIaXHNGplxX6g4kgxF+tOTdA9gQtkqQTlSPEdg4bdUCMqWKv4Q GAOG1fm9tJZjinR9s4g== X-Received: by 2002:a05:622a:1889:: with SMTP id v9mr3217150qtc.48.1633965434290; Mon, 11 Oct 2021 08:17:14 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwFFG8opMUni5U5qgBwq0mlogwioJV/XkJHYqcDbK1Y3OpPB0RIPULZZrLCzfJGUzVGrgh8Uw== X-Received: by 2002:a05:622a:1889:: with SMTP id v9mr3217077qtc.48.1633965433695; Mon, 11 Oct 2021 08:17:13 -0700 (PDT) Received: from redhat.com ([2601:184:4780:4310::9b82]) by smtp.gmail.com with ESMTPSA id m68sm4369086qkb.105.2021.10.11.08.17.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 11 Oct 2021 08:17:13 -0700 (PDT) Date: Mon, 11 Oct 2021 11:17:11 -0400 From: Marek Polacek To: Jason Merrill Cc: Jakub Jelinek , GCC Patches Subject: Re: [PATCH v4] attribs: Implement -Wno-attributes=vendor::attr [PR101940] Message-ID: References: <20210920170658.28014-1-polacek@redhat.com> <20210920173859.GK304296@tucnak> <20210920190809.GM304296@tucnak> <8636350f-e588-12d1-b687-89245de0b62d@redhat.com> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/2.0.7 (2021-05-04) 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_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-List-Received-Date: Mon, 11 Oct 2021 15:17:21 -0000 Ping. On Tue, Sep 28, 2021 at 04:20:46PM -0400, Marek Polacek wrote: > On Thu, Sep 23, 2021 at 02:25:16PM -0400, Jason Merrill wrote: > > On 9/20/21 18:59, Marek Polacek via Gcc-patches wrote: > > > +void > > > +handle_ignored_attributes_option (vec *v) > > > +{ > > > + if (v == nullptr) > > > + return; > > > + > > > + for (auto opt : v) > > > + { > > > + if (strcmp (opt, "clang") == 0) > > > + { > > > + // TODO > > > + continue; > > > + } > > > > If this doesn't work yet, let's not accept it at all for now. > > Ok. > > > > + char *q = strstr (opt, "::"); > > > + /* We don't accept '::attr'. */ > > > + if (q == nullptr || q == opt) > > > + { > > > + error ("wrong argument to ignored attributes"); > > > + inform (input_location, "valid format is %, %, " > > > + "or %"); > > > > ...or even mention it. Users can ignore clang:: instead, it doesn't matter > > to us if clang attributes are misspelled. > > Removed. > > > > + continue; > > > + } > > > + /* Cut off the vendor part. */ > > > + *q = '\0'; > > > + char *vendor = opt; > > > + char *attr = q + 2; > > > + /* Verify that they look valid. */ > > > + auto valid_p = [](const char *s) { > > > + for (; *s != '\0'; ++s) > > > + if (!ISALNUM (*s) && *s != '_') > > > + return false; > > > + return true; > > > + }; > > > + if (!valid_p (vendor) || !valid_p (attr)) > > > + { > > > + error ("wrong argument to ignored attributes"); > > > + continue; > > > + } > > > + /* Turn "__attr__" into "attr" so that we have a canonical form of > > > + attribute names. Likewise for vendor. */ > > > + auto strip = [](char *&s) { > > > + const size_t l = strlen (s); > > > + if (l > 4 && s[0] == '_' && s[1] == '_' > > > + && s[l - 1] == '_' && s[l - 2] == '_') > > > + { > > > + s[l - 2] = '\0'; > > > + s += 2; > > > + } > > > + }; > > > + strip (attr); > > > + strip (vendor); > > > + /* If we've already seen this vendor::attr, ignore it. Attempting to > > > + register it twice would lead to a crash. */ > > > + if (lookup_scoped_attribute_spec (get_identifier (vendor), > > > + get_identifier (attr))) > > > + continue; > > > + /* In the "vendor::" case, we should ignore *any* attribute coming > > > + from this attribute namespace. */ > > > + const bool ignored_ns = attr[0] == '\0'; > > > > Maybe set attr to nullptr instead of declaring ignored_ns? > > > > > + /* Create a table with extra attributes which we will register. > > > + 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] = { ignored_ns ? nullptr : attr, 0, 0, false, false, > > > > ...so this can just use attr. > > I also need ignored_ns... > > > > + false, false, nullptr, nullptr }; > > > + table[1] = { nullptr, 0, 0, false, false, false, false, nullptr, nullptr }; > > > + register_scoped_attributes (table, vendor, ignored_ns); > > ...here, but I tweaked this a bit to get rid of the bool. > > > > + } > > > +} > > > + > > > +/* Free data we might have allocated when adding extra attributes. */ > > > + > > > +void > > > +free_attr_data () > > > +{ > > > + for (auto x : ignored_attributes_table) > > > + delete[] x; > > > +} > > > > You probably also want to zero out ignored_attributes_table at this point. > > Done. > > > > /* Initialize attribute tables, and make some sanity checks if checking is > > > enabled. */ > > > @@ -252,6 +353,9 @@ init_attributes (void) > > > /* Put all the GNU attributes into the "gnu" namespace. */ > > > register_scoped_attributes (attribute_tables[i], "gnu"); > > > + vec *ignored = (vec *) flag_ignored_attributes; > > > + handle_ignored_attributes_option (ignored); > > > + > > > invoke_plugin_callbacks (PLUGIN_ATTRIBUTES, NULL); > > > attributes_initialized = true; > > > } > > > @@ -456,6 +560,19 @@ diag_attr_exclusions (tree last_decl, tree node, tree attrname, > > > return found; > > > } > > > +/* Return true iff we should not complain about unknown attributes > > > + coming from the attribute namespace NS. This is the case for > > > + the -Wno-attributes=ns:: command-line option. */ > > > + > > > +static bool > > > +attr_namespace_ignored_p (tree ns) > > > +{ > > > + if (ns == NULL_TREE) > > > + return false; > > > + scoped_attributes *r = find_attribute_namespace (IDENTIFIER_POINTER (ns)); > > > + return r && r->ignored_p; > > > +} > > > + > > > /* Process the attributes listed in ATTRIBUTES and install them in *NODE, > > > which is either a DECL (including a TYPE_DECL) or a TYPE. If a DECL, > > > it should be modified in place; if a TYPE, a copy should be created > > > @@ -556,7 +673,8 @@ decl_attributes (tree *node, tree attributes, int flags, > > > if (spec == NULL) > > > { > > > - if (!(flags & (int) ATTR_FLAG_BUILT_IN)) > > > + if (!(flags & (int) ATTR_FLAG_BUILT_IN) > > > + && !attr_namespace_ignored_p (ns)) > > > { > > > if (ns == NULL_TREE || !cxx11_attr_p) > > > warning (OPT_Wattributes, "%qE attribute directive ignored", > > > diff --git a/gcc/attribs.h b/gcc/attribs.h > > > index 138c509bce1..96a527f67a9 100644 > > > --- a/gcc/attribs.h > > > +++ b/gcc/attribs.h > > > @@ -21,6 +21,7 @@ along with GCC; see the file COPYING3. If not see > > > #define GCC_ATTRIBS_H > > > extern const struct attribute_spec *lookup_attribute_spec (const_tree); > > > +extern void free_attr_data (); > > > extern void init_attributes (void); > > > /* Process the attributes listed in ATTRIBUTES and install them in *NODE, > > > @@ -40,12 +41,14 @@ extern void apply_tm_attr (tree, tree); > > > extern tree make_attribute (const char *, const char *, tree); > > > extern struct scoped_attributes* register_scoped_attributes (const struct attribute_spec *, > > > - const char *); > > > + const char *, > > > + bool = false); > > > extern char *sorted_attr_string (tree); > > > extern bool common_function_versions (tree, tree); > > > extern tree make_dispatcher_decl (const tree); > > > extern bool is_function_default_version (const tree); > > > +extern void handle_ignored_attributes_option (vec *); > > > /* Return a type like TTYPE except that its TYPE_ATTRIBUTES > > > is ATTRIBUTE. > > > diff --git a/gcc/c-family/c-pragma.c b/gcc/c-family/c-pragma.c > > > index a9be8df0384..6beba5503f0 100644 > > > --- a/gcc/c-family/c-pragma.c > > > +++ b/gcc/c-family/c-pragma.c > > > @@ -764,7 +764,7 @@ handle_pragma_diagnostic(cpp_reader *ARG_UNUSED(dummy)) > > > if (token != CPP_NAME) > > > { > > > warning_at (loc, OPT_Wpragmas, > > > - "missing [error|warning|ignored|push|pop]" > > > + "missing [error|warning|ignored|push|pop|ignored_attributes]" > > > " after %<#pragma GCC diagnostic%>"); > > > return; > > > } > > > @@ -787,10 +787,43 @@ handle_pragma_diagnostic(cpp_reader *ARG_UNUSED(dummy)) > > > diagnostic_pop_diagnostics (global_dc, input_location); > > > return; > > > } > > > + else if (strcmp (kind_string, "ignored_attributes") == 0) > > > + { > > > + token = pragma_lex (&x, &loc); > > > + if (token != CPP_STRING) > > > + { > > > + warning_at (loc, OPT_Wpragmas, > > > + "missing attribute name after %<#pragma GCC diagnostic " > > > + "ignored_attributes%>"); > > > + return; > > > + } > > > + char *args = xstrdup (TREE_STRING_POINTER (x)); > > > + const size_t l = strlen (args); > > > + if (l == 0) > > > + { > > > + warning_at (loc, OPT_Wpragmas, "missing argument to %<#pragma GCC " > > > + "diagnostic ignored_attributes%>"); > > > + free (args); > > > + return; > > > + } > > > + else if (args[l - 1] == ',') > > > + { > > > + warning_at (loc, OPT_Wpragmas, "trailing %<,%> in arguments for " > > > + "%<#pragma GCC diagnostic ignored_attributes%>"); > > > + free (args); > > > + return; > > > + } > > > + auto_vec v; > > > + for (char *p = strtok (args, ","); p; p = strtok (NULL, ",")) > > > + v.safe_push (p); > > > + handle_ignored_attributes_option (&v); > > > + /* ??? We can't free (args); here. */ > > > > Perhaps we want to copy strings in handle_ignored_attributes_option rather > > than here? > > Well, the other use doesn't need copying, so I left it be. > > > > + return; > > > + } > > > else > > > { > > > warning_at (loc, OPT_Wpragmas, > > > - "expected [error|warning|ignored|push|pop]" > > > + "expected [error|warning|ignored|push|pop|ignored_attributes]" > > > " after %<#pragma GCC diagnostic%>"); > > > return; > > > } > > > diff --git a/gcc/c/c-decl.c b/gcc/c/c-decl.c > > > index 771efa3eadf..345c8f9d620 100644 > > > --- a/gcc/c/c-decl.c > > > +++ b/gcc/c/c-decl.c > > > @@ -12295,6 +12295,8 @@ c_parse_final_cleanups (void) > > > c_write_global_declarations_1 (BLOCK_VARS (DECL_INITIAL (t))); > > > c_write_global_declarations_1 (BLOCK_VARS (ext_block)); > > > + free_attr_data (); > > > > Since handle_ignored_attributes_option is in language-independent code, > > shouldn't this call be as well? > > Good point, I've moved it into compile_file. I don't where else it could > have gone. > > Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk? > > -- >8 -- > It is desirable for -Wattributes to warn about e.g. > > [[deprecate]] void g(); // typo, should warn > > However, -Wattributes also warns about vendor-specific attributes > (that's because lookup_scoped_attribute_spec -> find_attribute_namespace > finds nothing), which, with -Werror, causes grief. We don't want the > -Wattributes warning for > > [[company::attr]] void f(); > > GCC warns because it doesn't know the "company" namespace; it only knows > the "gnu" and "omp" namespaces. We could entirely disable warning about > attributes in unknown scopes but then the compiler would also miss typos > like > > [[company::attrx]] void f(); > > or > > [[gmu::warn_used_result]] int write(); > > so that is not a viable solution. A workaround is to use a #pragma: > > #pragma GCC diagnostic push > #pragma GCC diagnostic ignored "-Wattributes" > [[company::attr]] void f() {} > #pragma GCC diagnostic pop > > but that's a mouthful and awkward to use and could also hide typos. In > fact, any macro-based solution doesn't seem like a way forward. > > This patch implements -Wno-attributes=, which takes these arguments: > > company::attr > company:: > > This option should go well with using @file: the user could have a file > containing > -Wno-attributes=vendor::attr1,vendor::attr2 > and then invoke gcc with '@attrs' or similar. > > I've also added a new pragma which has the same effect: > > The pragma along with the new option should help with various static > analysis tools. > > PR c++/101940 > > gcc/ChangeLog: > > * attribs.c (struct scoped_attributes): Add a bool member. > (lookup_scoped_attribute_spec): Forward declare. > (register_scoped_attributes): New bool parameter, defaulted to > false. Use it. > (handle_ignored_attributes_option): New function. > (free_attr_data): New function. > (init_attributes): Call handle_ignored_attributes_option. > (attr_namespace_ignored_p): New function. > (decl_attributes): Check attr_namespace_ignored_p before > warning. > * attribs.h (free_attr_data): Declare. > (register_scoped_attributes): Adjust declaration. > (handle_ignored_attributes_option): Declare. > * common.opt (Wattributes=): New option with a variable. > * doc/extend.texi: Document #pragma GCC diagnostic ignored_attributes. > * doc/invoke.texi: Document -Wno-attributes=. > * opts.c (common_handle_option) : Handle. > * plugin.h (register_scoped_attributes): Adjust declaration. > > gcc/c-family/ChangeLog: > > * c-pragma.c (handle_pragma_diagnostic): Handle #pragma GCC diagnostic > ignored_attributes. > > gcc/c/ChangeLog: > > * c-decl.c (c_parse_final_cleanups): Call free_attr_data. > > gcc/cp/ChangeLog: > > * decl2.c (c_parse_final_cleanups): Call free_attr_data. > > gcc/testsuite/ChangeLog: > > * c-c++-common/Wno-attributes-1.c: New test. > * c-c++-common/Wno-attributes-2.c: New test. > --- > gcc/attribs.c | 120 +++++++++++++++++- > gcc/attribs.h | 5 +- > gcc/c-family/c-pragma.c | 37 +++++- > gcc/common.opt | 9 +- > gcc/doc/extend.texi | 19 +++ > gcc/doc/invoke.texi | 20 +++ > gcc/opts.c | 20 +++ > gcc/plugin.h | 4 +- > gcc/testsuite/c-c++-common/Wno-attributes-1.c | 55 ++++++++ > gcc/testsuite/c-c++-common/Wno-attributes-2.c | 56 ++++++++ > gcc/toplev.c | 2 + > 11 files changed, 338 insertions(+), 9 deletions(-) > create mode 100644 gcc/testsuite/c-c++-common/Wno-attributes-1.c > create mode 100644 gcc/testsuite/c-c++-common/Wno-attributes-2.c > > diff --git a/gcc/attribs.c b/gcc/attribs.c > index 83fafc98b7d..d5fba7f4bbb 100644 > --- a/gcc/attribs.c > +++ b/gcc/attribs.c > @@ -87,6 +87,8 @@ struct scoped_attributes > const char *ns; > vec attributes; > hash_table *attribute_hash; > + /* True if we should not warn about unknown attributes in this NS. */ > + bool ignored_p; > }; > > /* The table of scope attributes. */ > @@ -95,6 +97,8 @@ static vec attributes_table; > static scoped_attributes* find_attribute_namespace (const char*); > static void register_scoped_attribute (const struct attribute_spec *, > scoped_attributes *); > +static const struct attribute_spec *lookup_scoped_attribute_spec (const_tree, > + const_tree); > > static bool attributes_initialized = false; > > @@ -121,12 +125,14 @@ extract_attribute_substring (struct substring *str) > > /* Insert an array of attributes ATTRIBUTES into a namespace. This > array must be NULL terminated. NS is the name of attribute > - namespace. The function returns the namespace into which the > - attributes have been registered. */ > + namespace. IGNORED_P is true iff all unknown attributes in this > + namespace should be ignored for the purposes of -Wattributes. The > + function returns the namespace into which the attributes have been > + registered. */ > > scoped_attributes * > register_scoped_attributes (const struct attribute_spec *attributes, > - const char *ns) > + const char *ns, bool ignored_p /*=false*/) > { > scoped_attributes *result = NULL; > > @@ -144,9 +150,12 @@ register_scoped_attributes (const struct attribute_spec *attributes, > memset (&sa, 0, sizeof (sa)); > sa.ns = ns; > sa.attributes.create (64); > + sa.ignored_p = ignored_p; > result = attributes_table.safe_push (sa); > result->attribute_hash = new hash_table (200); > } > + else > + result->ignored_p |= ignored_p; > > /* Really add the attributes to their namespace now. */ > for (unsigned i = 0; attributes[i].name != NULL; ++i) > @@ -224,6 +233,92 @@ check_attribute_tables (void) > attribute_tables[j][l].name)); > } > > +/* Used to stash pointers to allocated memory so that we can free them at > + the end of parsing of all TUs. */ > +static vec ignored_attributes_table; > + > +/* Parse arguments ARGS of -Wno-attributes=. > + Currently we accept: > + vendor::attr > + vendor:: > + This functions also registers the parsed attributes so that we don't > + warn that we don't recognize them. */ > + > +void > +handle_ignored_attributes_option (vec *v) > +{ > + if (v == nullptr) > + return; > + > + for (auto opt : v) > + { > + char *q = strstr (opt, "::"); > + /* We don't accept '::attr'. */ > + if (q == nullptr || q == opt) > + { > + error ("wrong argument to ignored attributes"); > + inform (input_location, "valid format is % or %"); > + continue; > + } > + /* Cut off the vendor part. */ > + *q = '\0'; > + char *vendor = opt; > + char *attr = q + 2; > + /* Verify that they look valid. */ > + auto valid_p = [](const char *s) { > + for (; *s != '\0'; ++s) > + if (!ISALNUM (*s) && *s != '_') > + return false; > + return true; > + }; > + if (!valid_p (vendor) || !valid_p (attr)) > + { > + error ("wrong argument to ignored attributes"); > + continue; > + } > + /* Turn "__attr__" into "attr" so that we have a canonical form of > + attribute names. Likewise for vendor. */ > + auto strip = [](char *&s) { > + const size_t l = strlen (s); > + if (l > 4 && s[0] == '_' && s[1] == '_' > + && s[l - 1] == '_' && s[l - 2] == '_') > + { > + s[l - 2] = '\0'; > + s += 2; > + } > + }; > + strip (attr); > + strip (vendor); > + /* If we've already seen this vendor::attr, ignore it. Attempting to > + register it twice would lead to a crash. */ > + if (lookup_scoped_attribute_spec (get_identifier (vendor), > + get_identifier (attr))) > + continue; > + /* In the "vendor::" case, we should ignore *any* attribute coming > + from this attribute namespace. */ > + if (attr[0] == '\0') > + attr = nullptr; > + /* Create a table with extra attributes which we will register. > + 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[1] = { nullptr, 0, 0, false, false, false, false, nullptr, > + nullptr }; > + register_scoped_attributes (table, vendor, !attr); > + } > +} > + > +/* Free data we might have allocated when adding extra attributes. */ > + > +void > +free_attr_data () > +{ > + for (auto x : ignored_attributes_table) > + delete[] x; > + ignored_attributes_table.release (); > +} > + > /* Initialize attribute tables, and make some sanity checks if checking is > enabled. */ > > @@ -252,6 +347,9 @@ init_attributes (void) > /* Put all the GNU attributes into the "gnu" namespace. */ > register_scoped_attributes (attribute_tables[i], "gnu"); > > + vec *ignored = (vec *) flag_ignored_attributes; > + handle_ignored_attributes_option (ignored); > + > invoke_plugin_callbacks (PLUGIN_ATTRIBUTES, NULL); > attributes_initialized = true; > } > @@ -456,6 +554,19 @@ diag_attr_exclusions (tree last_decl, tree node, tree attrname, > return found; > } > > +/* Return true iff we should not complain about unknown attributes > + coming from the attribute namespace NS. This is the case for > + the -Wno-attributes=ns:: command-line option. */ > + > +static bool > +attr_namespace_ignored_p (tree ns) > +{ > + if (ns == NULL_TREE) > + return false; > + scoped_attributes *r = find_attribute_namespace (IDENTIFIER_POINTER (ns)); > + return r && r->ignored_p; > +} > + > /* Process the attributes listed in ATTRIBUTES and install them in *NODE, > which is either a DECL (including a TYPE_DECL) or a TYPE. If a DECL, > it should be modified in place; if a TYPE, a copy should be created > @@ -556,7 +667,8 @@ decl_attributes (tree *node, tree attributes, int flags, > > if (spec == NULL) > { > - if (!(flags & (int) ATTR_FLAG_BUILT_IN)) > + if (!(flags & (int) ATTR_FLAG_BUILT_IN) > + && !attr_namespace_ignored_p (ns)) > { > if (ns == NULL_TREE || !cxx11_attr_p) > warning (OPT_Wattributes, "%qE attribute directive ignored", > diff --git a/gcc/attribs.h b/gcc/attribs.h > index 138c509bce1..96a527f67a9 100644 > --- a/gcc/attribs.h > +++ b/gcc/attribs.h > @@ -21,6 +21,7 @@ along with GCC; see the file COPYING3. If not see > #define GCC_ATTRIBS_H > > extern const struct attribute_spec *lookup_attribute_spec (const_tree); > +extern void free_attr_data (); > extern void init_attributes (void); > > /* Process the attributes listed in ATTRIBUTES and install them in *NODE, > @@ -40,12 +41,14 @@ extern void apply_tm_attr (tree, tree); > extern tree make_attribute (const char *, const char *, tree); > > extern struct scoped_attributes* register_scoped_attributes (const struct attribute_spec *, > - const char *); > + const char *, > + bool = false); > > extern char *sorted_attr_string (tree); > extern bool common_function_versions (tree, tree); > extern tree make_dispatcher_decl (const tree); > extern bool is_function_default_version (const tree); > +extern void handle_ignored_attributes_option (vec *); > > /* Return a type like TTYPE except that its TYPE_ATTRIBUTES > is ATTRIBUTE. > diff --git a/gcc/c-family/c-pragma.c b/gcc/c-family/c-pragma.c > index a9be8df0384..6beba5503f0 100644 > --- a/gcc/c-family/c-pragma.c > +++ b/gcc/c-family/c-pragma.c > @@ -764,7 +764,7 @@ handle_pragma_diagnostic(cpp_reader *ARG_UNUSED(dummy)) > if (token != CPP_NAME) > { > warning_at (loc, OPT_Wpragmas, > - "missing [error|warning|ignored|push|pop]" > + "missing [error|warning|ignored|push|pop|ignored_attributes]" > " after %<#pragma GCC diagnostic%>"); > return; > } > @@ -787,10 +787,43 @@ handle_pragma_diagnostic(cpp_reader *ARG_UNUSED(dummy)) > diagnostic_pop_diagnostics (global_dc, input_location); > return; > } > + else if (strcmp (kind_string, "ignored_attributes") == 0) > + { > + token = pragma_lex (&x, &loc); > + if (token != CPP_STRING) > + { > + warning_at (loc, OPT_Wpragmas, > + "missing attribute name after %<#pragma GCC diagnostic " > + "ignored_attributes%>"); > + return; > + } > + char *args = xstrdup (TREE_STRING_POINTER (x)); > + const size_t l = strlen (args); > + if (l == 0) > + { > + warning_at (loc, OPT_Wpragmas, "missing argument to %<#pragma GCC " > + "diagnostic ignored_attributes%>"); > + free (args); > + return; > + } > + else if (args[l - 1] == ',') > + { > + warning_at (loc, OPT_Wpragmas, "trailing %<,%> in arguments for " > + "%<#pragma GCC diagnostic ignored_attributes%>"); > + free (args); > + return; > + } > + auto_vec v; > + for (char *p = strtok (args, ","); p; p = strtok (NULL, ",")) > + v.safe_push (p); > + handle_ignored_attributes_option (&v); > + /* ??? We can't free (args); here. */ > + return; > + } > else > { > warning_at (loc, OPT_Wpragmas, > - "expected [error|warning|ignored|push|pop]" > + "expected [error|warning|ignored|push|pop|ignored_attributes]" > " after %<#pragma GCC diagnostic%>"); > return; > } > diff --git a/gcc/common.opt b/gcc/common.opt > index a9644cae4f0..c429e43c6c1 100644 > --- a/gcc/common.opt > +++ b/gcc/common.opt > @@ -83,7 +83,7 @@ int flag_gen_aux_info = 0 > Variable > int flag_shlib > > -; These two are really VEC(char_p,heap) *. > +; These three are really VEC(char_p,heap) *. > > Variable > void *flag_instrument_functions_exclude_functions > @@ -91,6 +91,9 @@ void *flag_instrument_functions_exclude_functions > Variable > void *flag_instrument_functions_exclude_files > > +Variable > +void *flag_ignored_attributes > + > ; Generic structs (e.g. templates not explicitly specialized) > ; may not have a compilation unit associated with them, and so > ; may need to be treated differently from ordinary structs. > @@ -549,6 +552,10 @@ Wattributes > Common Var(warn_attributes) Init(1) Warning > Warn about inappropriate attribute usage. > > +Wattributes= > +Common Joined > +Do not warn about specified attributes. > + > Wattribute-alias > Common Alias(Wattribute_alias=, 1, 0) Warning > Warn about type safety and similar errors and mismatches in declarations with alias attributes. > diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi > index b4c5376223a..28fd0cc6dd5 100644 > --- a/gcc/doc/extend.texi > +++ b/gcc/doc/extend.texi > @@ -23761,6 +23761,25 @@ restored. > foo(d); /* depends on command-line options */ > @end smallexample > > +@item #pragma GCC diagnostic ignored_attributes > + > +Similarly to @option{-Wno-attributes=}, this pragma allows users to suppress > +warnings about unknown scoped attributes (in C++11 and C2X). For example, > +@code{#pragma GCC diagnostic ignored_attributes "vendor::attr"} disables > +warning about the following declaration: > + > +@smallexample > +[[vendor::attr]] void f(); > +@end smallexample > + > +whereas @code{#pragma GCC diagnostic ignored_attributes "vendor::"} prevents > +warning about both of these declarations: > + > +@smallexample > +[[vendor::safe]] void f(); > +[[vendor::unsafe]] void f2(); > +@end smallexample > + > @end table > > GCC also offers a simple mechanism for printing messages during > diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi > index 5b016166972..fe2cb768c61 100644 > --- a/gcc/doc/invoke.texi > +++ b/gcc/doc/invoke.texi > @@ -8623,6 +8623,26 @@ unrecognized attributes, function attributes applied to variables, > etc. This does not stop errors for incorrect use of supported > attributes. > > +Additionally, using @option{-Wno-attributes=}, it is possible to suppress > +warnings about unknown scoped attributes (in C++11 and C2X). For example, > +@option{-Wno-attributes=vendor::attr} disables warning about the following > +declaration: > + > +@smallexample > +[[vendor::attr]] void f(); > +@end smallexample > + > +It is also possible to disable warning about all attributes in a namespace > +using @option{-Wno-attributes=vendor::} which prevents warning about both > +of these declarations: > + > +@smallexample > +[[vendor::safe]] void f(); > +[[vendor::unsafe]] void f2(); > +@end smallexample > + > +Note that @option{-Wno-attributes=} does not imply @option{-Wno-attributes}. > + > @item -Wno-builtin-declaration-mismatch > @opindex Wno-builtin-declaration-mismatch > @opindex Wbuiltin-declaration-mismatch > diff --git a/gcc/opts.c b/gcc/opts.c > index 6503980cd33..e3b66ad0d43 100644 > --- a/gcc/opts.c > +++ b/gcc/opts.c > @@ -2558,6 +2558,26 @@ common_handle_option (struct gcc_options *opts, > /* Currently handled in a prescan. */ > break; > > + case OPT_Wattributes_: > + if (lang_mask == CL_DRIVER) > + break; > + > + if (value) > + { > + error_at (loc, "arguments ignored for %<-Wattributes=%>; use " > + "%<-Wno-attributes=%> instead"); > + break; > + } > + else if (arg[strlen (arg) - 1] == ',') > + { > + error_at (loc, "trailing %<,%> in arguments for " > + "%<-Wno-attributes=%>"); > + break; > + } > + > + add_comma_separated_to_vector (&opts->x_flag_ignored_attributes, arg); > + break; > + > case OPT_Werror: > dc->warning_as_error_requested = value; > break; > diff --git a/gcc/plugin.h b/gcc/plugin.h > index 1640e253ca5..5556763d1bf 100644 > --- a/gcc/plugin.h > +++ b/gcc/plugin.h > @@ -197,7 +197,9 @@ invoke_plugin_callbacks (int event ATTRIBUTE_UNUSED, > /* In attribs.c. */ > > extern void register_attribute (const struct attribute_spec *attr); > +/* The default argument for the third parameter is given in attribs.h. */ > extern struct scoped_attributes* register_scoped_attributes (const struct attribute_spec *, > - const char *); > + const char *, > + bool); > > #endif /* PLUGIN_H */ > diff --git a/gcc/testsuite/c-c++-common/Wno-attributes-1.c b/gcc/testsuite/c-c++-common/Wno-attributes-1.c > new file mode 100644 > index 00000000000..aac1a69fd85 > --- /dev/null > +++ b/gcc/testsuite/c-c++-common/Wno-attributes-1.c > @@ -0,0 +1,55 @@ > +/* PR c++/101940 */ > +/* { dg-do compile } */ > +/* { dg-additional-options "-std=c++11" { target c++ } } */ > +/* { dg-additional-options "-Wno-attributes=company::,yoyodyne::attr" } */ > +/* { dg-additional-options "-Wno-attributes=c1::attr,c1::attr,c1::__attr__" } */ > +/* { dg-additional-options "-Wno-attributes=c2::,c2::attr" } */ > +/* { dg-additional-options "-Wno-attributes=c3::attr,c3::" } */ > +/* { dg-additional-options "-Wno-attributes=x::" } */ > +/* { dg-additional-options "-Wno-attributes=yoyodyne::attr_new" } */ > +/* { dg-additional-options "-Wno-attributes=c4::__attr__" } */ > +/* { dg-additional-options "-Wno-attributes=c5::attr" } */ > +/* { dg-additional-options "-Wno-attributes=__c6__::attr" } */ > + > +[[company::attr]] void f1(); > +[[company::attr2]] void f2(); > + > +[[yoyodyne::attr]] void f3(); > +[[yoyodyne::__attr__]] void f3__(); > +[[yoyodyne::attrx]] void f4(); /* { dg-warning "ignored" } */ > +[[yoyodyne::__attrx__]] void f4__(); /* { dg-warning "ignored" } */ > + > +[[c1::attr]] void f5(); > + > +[[c2::attr]] void f6(); > +[[c2::attrx]] void f7(); > +[[c2::__attr__]] void f6__(); > +[[c2::__attrx__]] void f7__(); > + > +[[c3::attr]] void f8(); > +[[c3::attrx]] void f9(); > + > +[[x::x]] void f10(); > + > +[[yoyodyne::attr_new]] void f11(); > +[[yoyodyne::__attr_new__]] void f11__(); > +[[yoyodyne::attr_mew]] void f12(); /* { dg-warning "ignored" } */ > +[[yoyodyne::__attr_mew__]] void f12__(); /* { dg-warning "ignored" } */ > + > +[[c4::attr]] void f13(); > +[[c4::__attr__]] void f13__(); > +[[c4::attrx]] void f14(); /* { dg-warning "ignored" } */ > + > +[[c5::attr]] void f15(); > +[[c5::__attr__]] void f15__(); > +[[__c5__::attr]] void __f15(); > +[[__c5__::__attr__]] void __f15__(); > +[[c5::attrx]] void f15x(); /* { dg-warning "ignored" } */ > +[[__c5__::attrx]] void f15x(); /* { dg-warning "ignored" } */ > + > +[[c6::attr]] void f16(); > +[[c6::__attr__]] void f16__(); > +[[__c6__::attr]] void __f16(); > +[[__c6__::__attr__]] void __f16__(); > +[[c6::attrx]] void f16x(); /* { dg-warning "ignored" } */ > +[[__c6__::attrx]] void f16x(); /* { dg-warning "ignored" } */ > diff --git a/gcc/testsuite/c-c++-common/Wno-attributes-2.c b/gcc/testsuite/c-c++-common/Wno-attributes-2.c > new file mode 100644 > index 00000000000..4307c74b048 > --- /dev/null > +++ b/gcc/testsuite/c-c++-common/Wno-attributes-2.c > @@ -0,0 +1,56 @@ > +/* PR c++/101940 */ > +/* { dg-do compile } */ > +/* { dg-additional-options "-std=c++11" { target c++ } } */ > + > +#pragma GCC diagnostic ignored_attributes "company::,yoyodyne::attr" > +#pragma GCC diagnostic ignored_attributes "c1::attr,c1::attr,c1::__attr__" > +#pragma GCC diagnostic ignored_attributes "c2::,c2::attr" > +#pragma GCC diagnostic ignored_attributes "c3::attr,c3::" > +#pragma GCC diagnostic ignored_attributes "x::" > +#pragma GCC diagnostic ignored_attributes "yoyodyne::attr_new" > +#pragma GCC diagnostic ignored_attributes "c4::__attr__" > +#pragma GCC diagnostic ignored_attributes "c5::attr" > +#pragma GCC diagnostic ignored_attributes "__c6__::attr" > + > +[[company::attr]] void f1(); > +[[company::attr2]] void f2(); > + > +[[yoyodyne::attr]] void f3(); > +[[yoyodyne::__attr__]] void f3__(); > +[[yoyodyne::attrx]] void f4(); /* { dg-warning "ignored" } */ > +[[yoyodyne::__attrx__]] void f4__(); /* { dg-warning "ignored" } */ > + > +[[c1::attr]] void f5(); > + > +[[c2::attr]] void f6(); > +[[c2::attrx]] void f7(); > +[[c2::__attr__]] void f6__(); > +[[c2::__attrx__]] void f7__(); > + > +[[c3::attr]] void f8(); > +[[c3::attrx]] void f9(); > + > +[[x::x]] void f10(); > + > +[[yoyodyne::attr_new]] void f11(); > +[[yoyodyne::__attr_new__]] void f11__(); > +[[yoyodyne::attr_mew]] void f12(); /* { dg-warning "ignored" } */ > +[[yoyodyne::__attr_mew__]] void f12__(); /* { dg-warning "ignored" } */ > + > +[[c4::attr]] void f13(); > +[[c4::__attr__]] void f13__(); > +[[c4::attrx]] void f14(); /* { dg-warning "ignored" } */ > + > +[[c5::attr]] void f15(); > +[[c5::__attr__]] void f15__(); > +[[__c5__::attr]] void __f15(); > +[[__c5__::__attr__]] void __f15__(); > +[[c5::attrx]] void f15x(); /* { dg-warning "ignored" } */ > +[[__c5__::attrx]] void f15x(); /* { dg-warning "ignored" } */ > + > +[[c6::attr]] void f16(); > +[[c6::__attr__]] void f16__(); > +[[__c6__::attr]] void __f16(); > +[[__c6__::__attr__]] void __f16__(); > +[[c6::attrx]] void f16x(); /* { dg-warning "ignored" } */ > +[[__c6__::attrx]] void f16x(); /* { dg-warning "ignored" } */ > diff --git a/gcc/toplev.c b/gcc/toplev.c > index e1688aae724..f5ccaf8f799 100644 > --- a/gcc/toplev.c > +++ b/gcc/toplev.c > @@ -463,6 +463,8 @@ compile_file (void) > if (flag_dump_locations) > dump_location_info (stderr); > > + free_attr_data (); > + > /* Compilation is now finished except for writing > what's left of the symbol table output. */ > > > base-commit: a11052d98db2f2a61841f0c5ee84de4ca1b3e296 > -- > 2.31.1 > Marek