From patchwork Tue Sep 28 20:20:46 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marek Polacek X-Patchwork-Id: 45534 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 76902385803C for ; Tue, 28 Sep 2021 20:22:39 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 76902385803C DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1632860559; bh=KNyvW1eAVmbvlEseJ7Y3m6Jeu+6eCXv/9w5UuVsp8Fk=; 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=noDMB00Qg+ESLweYCejxKYIyxj74VlgEQzpgcDDi+8J+MhmDW6rieBt8QpG0Jd2ls IA+mjW5YeCEMaXfBuYDodOSFa9vu2CigmKJSW5qv/mf0lbFO4lLysV2JAYLOy+xrOy 7Tz7GyGsbkDj2ekSyt99w4NMwo0/IASMCTEYAmB4= 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 [216.205.24.124]) by sourceware.org (Postfix) with ESMTP id D7E3B385803C for ; Tue, 28 Sep 2021 20:20:52 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org D7E3B385803C Received: from mail-qt1-f200.google.com (mail-qt1-f200.google.com [209.85.160.200]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-571-ASt_WqeRNfeiYivmUB3_IA-1; Tue, 28 Sep 2021 16:20:51 -0400 X-MC-Unique: ASt_WqeRNfeiYivmUB3_IA-1 Received: by mail-qt1-f200.google.com with SMTP id x28-20020ac8701c000000b0029f4b940566so149097qtm.19 for ; Tue, 28 Sep 2021 13:20:51 -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=KNyvW1eAVmbvlEseJ7Y3m6Jeu+6eCXv/9w5UuVsp8Fk=; b=JUh2UruxwZBcQ0yZNoOio6sEfa0n9lxF3muQ95g9WSxN5q+xziNALO6ftZ8XpRng8D gKu9CaDhBMIxywqYwKSr+9jmGXnuMvI3jnk33/vEHZqbQTYWoH/Oum4ilo4iIjZTAEcV RdEyJaVjctat1OvfmCIGWxpGU1M9yEK33a8B1jBlEZOWRsNpUCHaqc6k19ymO+Cs9v0k 1ZdsAS/Llf2iyY0GsipPyl+dWD2AFxxaEChsAZhsyu4KDsHIWdqWE951Y/6j+BAQ/SSc ZO7hoFB/gtFMWhsJ9vMf9zf+O4kpuWAwgetNbVpX5t2SnH/d1V0Tic0REBQ0o49BcGy5 0rNg== X-Gm-Message-State: AOAM531O0qK8rjhArzqWOq6XLdGZdANBAtTLj+KnI3sooFIBk2kJ/eBS FUsoTv9oN4iJ4AP7hnrwzq9Mv5As1c0EIDUYBFQto9J0W+NsSe6u+5VDGm86lzX7MNZVmk0dHn4 Jya1hD9GaZDdA1dWqxg== X-Received: by 2002:ac8:143:: with SMTP id f3mr8010694qtg.238.1632860449716; Tue, 28 Sep 2021 13:20:49 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyNFXYm9lwaBGwLvLpVNTFK07KoALKJl1gvDco2KA36NpSFU6v6J/VnO6GGSYlRoI6LcKctWg== X-Received: by 2002:ac8:143:: with SMTP id f3mr8010642qtg.238.1632860449051; Tue, 28 Sep 2021 13:20:49 -0700 (PDT) Received: from redhat.com ([2601:184:4780:4310::9b82]) by smtp.gmail.com with ESMTPSA id t24sm153068qkg.28.2021.09.28.13.20.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 28 Sep 2021 13:20:48 -0700 (PDT) Date: Tue, 28 Sep 2021 16:20:46 -0400 To: Jason Merrill Subject: [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: <8636350f-e588-12d1-b687-89245de0b62d@redhat.com> User-Agent: Mutt/2.0.7 (2021-05-04) X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com 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-Patchwork-Original-From: Marek Polacek via Gcc-patches From: Marek Polacek Reply-To: Marek Polacek Cc: Jakub Jelinek , GCC Patches Errors-To: gcc-patches-bounces+patchwork=sourceware.org@gcc.gnu.org Sender: "Gcc-patches" 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 base-commit: a11052d98db2f2a61841f0c5ee84de4ca1b3e296 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. */