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Tue, 09 Nov 2021 13:31:00 -0800 (PST) X-Google-Smtp-Source: ABdhPJwAE5osObOR/1lirYQfLCjmw9b1t8wJAkiRx2IsfD3vO7SzbTuZUl00LFB6ZpgAn5vnuU4kzw== X-Received: by 2002:a05:622a:28e:: with SMTP id z14mr12095886qtw.24.1636493459867; Tue, 09 Nov 2021 13:30:59 -0800 (PST) Received: from redhat.com ([2601:184:4780:4310::aac2]) by smtp.gmail.com with ESMTPSA id m1sm12600518qkp.124.2021.11.09.13.30.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 09 Nov 2021 13:30:59 -0800 (PST) Date: Tue, 9 Nov 2021 16:30:57 -0500 To: Jason Merrill Subject: [PATCH v8] attribs: Implement -Wno-attributes=vendor::attr [PR101940] Message-ID: References: <84D9B2CE-EA9B-46FB-9BF5-809D29B7018E@gmail.com> <516f3ddd-8634-9d73-ddd4-ae470f4284cf@redhat.com> <20211109080910.2eae4f69@nbbrfq> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/2.1.3 (2021-09-10) X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Disposition: inline X-Spam-Status: No, score=-13.4 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_H4, 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-Patchwork-Original-From: Marek Polacek via Gcc-patches From: Marek Polacek Reply-To: Marek Polacek Cc: Jakub Jelinek , Bernhard Reutner-Fischer , Marek Polacek via Gcc-patches Errors-To: gcc-patches-bounces+patchwork=sourceware.org@gcc.gnu.org Sender: "Gcc-patches" On Tue, Nov 09, 2021 at 02:17:14PM -0500, Marek Polacek wrote: > On Tue, Nov 09, 2021 at 12:27:28PM -0500, Jason Merrill wrote: > > On 11/9/21 10:55, Marek Polacek wrote: > > > On Tue, Nov 09, 2021 at 08:09:10AM +0100, Bernhard Reutner-Fischer wrote: > > > > On Tue, 9 Nov 2021 00:12:10 -0500 > > > > Jason Merrill wrote: > > > > > > > > > On 11/8/21 20:41, Marek Polacek wrote: > > > > > > On Sat, Nov 06, 2021 at 03:29:57PM -0400, Jason Merrill wrote: > > > > > > > > > > + for (auto opt : v) > > > > > > + { > > > > > > + char *cln = strstr (opt, "::"); > > > > > > + /* We don't accept '::attr'. */ > > > > > > + if (cln == nullptr || cln == opt) > > > > > > + { > > > > > > + error ("wrong argument to ignored attributes"); > > > > > > + inform (input_location, "valid format is % or %"); > > > > > > + continue; > > > > > > + } > > > > > > + char *vendor_start = opt; > > > > > > + ptrdiff_t vendor_len = cln - opt; > > > > > > + char *attr_start = cln + 2; > > > > > > + /* This could really use rawmemchr :(. */ > > > > > > + ptrdiff_t attr_len = strchr (attr_start, '\0') - attr_start; > > > > > > + /* Verify that they look valid. */ > > > > > > + auto valid_p = [](const char *const s, ptrdiff_t len) { > > > > > > + for (int i = 0; i < len; ++i) > > > > > > + if (!ISALNUM (*s) && *s != '_') > > > > > > + return false; > > > > > > + return true; > > > > > > + }; > > > > > > + if (!valid_p (vendor_start, vendor_len) > > > > > > + || !valid_p (attr_start, attr_len)) > > > > > > + { > > > > > > + 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, ptrdiff_t &l) { > > > > > > + if (l > 4 && s[0] == '_' && s[1] == '_' > > > > > > + && s[l - 1] == '_' && s[l - 2] == '_') > > > > > > + { > > > > > > + s += 2; > > > > > > + l -= 4; > > > > > > + } > > > > > > + }; > > > > > > + strip (attr_start, attr_len); > > > > > > + strip (vendor_start, vendor_len); > > > > > > + /* We perform all this hijinks so that we don't have to copy OPT. */ > > > > > > + tree vendor_id = get_identifier_with_length (vendor_start, vendor_len); > > > > > > + tree attr_id = get_identifier_with_length (attr_start, attr_len); > > > > > > + /* 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 (vendor_id, attr_id)) > > > > > > + continue; > > > > > > > > > > Hmm, this looks like it isn't handling the case of previously ignoring > > > > > vendor::; it seems we'll look for vendor:: instead, not > > > > > find it, and register again. > > > > > Yes, for -Wno-attributes=vendor::,vendor:: we call register_scoped_attributes > > > twice, but I think that's OK: register_scoped_attributes will see that > > > find_attribute_namespace finds the namespace and returns without > > > creating a new one. > > > > > > I think the current code handles -Wno-attributes=vendor::a,vendor:: well so > > > I'm not sure if I should change it. > > > > Makes sense. But we should be able to avoid calling > > lookup_scoped_attribute_spec, and even get_identifier_with_length (attr...), > > if attr_len is 0. > > Duh, of course. Also no need to canonicalize an empty string. > > > > > I don't know if there are __attrib with 2 leading underscores but no > > > > trailing that we accept and should normalize? > > > > > > > > And it is surprising that we do not have a simple normalize_attr_name(). > > > > There must be existing spots where we would normalize attribute names? > > > > extract_attribute_substring does about the same but with a struct substring(?). > > > > Maybe that's just to avoid a normal string hash. > > > > > > We have canonicalize_attr_name which I based my code on. > > > > We could factor out of that function an overload equivalent to your strip > > lambda? > > OK. Since it's taking a reference and I wanted it to work both with a size_t > and ptrdiff_t, I made it a template. Is is too much? OK, this time for real. Here's another version, which doesn't crash on -Wno-attributes=c::____. I apologize for the number of takes. :-( Bootstrap/regtest running on ppc64le-linux-gnu. OK if it passes? -- >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. (canonicalize_attr_name): New function template. (canonicalize_attr_name): Use it. * 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. * toplev.c (compile_file): Call free_attr_data. gcc/c-family/ChangeLog: * c-pragma.c (handle_pragma_diagnostic): Handle #pragma GCC diagnostic ignored_attributes. gcc/testsuite/ChangeLog: * c-c++-common/Wno-attributes-1.c: New test. * c-c++-common/Wno-attributes-2.c: New test. * c-c++-common/Wno-attributes-3.c: New test. --- gcc/attribs.c | 127 +++++++++++++++++- gcc/attribs.h | 28 +++- 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/testsuite/c-c++-common/Wno-attributes-3.c | 9 ++ gcc/toplev.c | 2 + 12 files changed, 374 insertions(+), 12 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 create mode 100644 gcc/testsuite/c-c++-common/Wno-attributes-3.c base-commit: 8875a92d31329ae52b734683784c4b054839a661 diff --git a/gcc/attribs.c b/gcc/attribs.c index 83fafc98b7d..0284e5bf2fd 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 +233,99 @@ 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 V 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 *cln = strstr (opt, "::"); + /* We don't accept '::attr'. */ + if (cln == nullptr || cln == opt) + { + error ("wrong argument to ignored attributes"); + inform (input_location, "valid format is % or %"); + continue; + } + const char *vendor_start = opt; + ptrdiff_t vendor_len = cln - opt; + const char *attr_start = cln + 2; + /* This could really use rawmemchr :(. */ + ptrdiff_t attr_len = strchr (attr_start, '\0') - attr_start; + /* Verify that they look valid. */ + auto valid_p = [](const char *const s, ptrdiff_t len) { + bool ok = false; + + for (int i = 0; i < len; ++i) + if (ISALNUM (s[i])) + ok = true; + else if (s[i] != '_') + return false; + + return ok; + }; + if (!valid_p (vendor_start, vendor_len)) + { + error ("wrong argument to ignored attributes"); + continue; + } + canonicalize_attr_name (vendor_start, vendor_len); + /* We perform all this hijinks so that we don't have to copy OPT. */ + tree vendor_id = get_identifier_with_length (vendor_start, vendor_len); + const char *attr; + /* In the "vendor::" case, we should ignore *any* attribute coming + from this attribute namespace. */ + if (attr_len > 0) + { + if (!valid_p (attr_start, attr_len)) + { + error ("wrong argument to ignored attributes"); + continue; + } + canonicalize_attr_name (attr_start, attr_len); + tree attr_id = get_identifier_with_length (attr_start, attr_len); + attr = IDENTIFIER_POINTER (attr_id); + /* 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 (vendor_id, attr_id)) + continue; + } + else + 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, IDENTIFIER_POINTER (vendor_id), !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 +354,9 @@ 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 +561,19 @@ 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 +674,8 @@ 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..ba657881940 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. @@ -114,17 +117,34 @@ extern unsigned decls_mismatched_attributes (tree, tree, tree, extern void maybe_diag_alias_attributes (tree, tree); +/* For a given string S of length L, strip leading and trailing '_' characters + so that we have a canonical form of attribute names. NB: This function may + change S and L. */ + +template +inline bool +canonicalize_attr_name (const char *&s, T &l) +{ + if (l > 4 && s[0] == '_' && s[1] == '_' && s[l - 1] == '_' && s[l - 2] == '_') + { + s += 2; + l -= 4; + return true; + } + return false; +} + /* For a given IDENTIFIER_NODE, strip leading and trailing '_' characters so that we have a canonical form of attribute names. */ static inline tree canonicalize_attr_name (tree attr_name) { - const size_t l = IDENTIFIER_LENGTH (attr_name); + size_t l = IDENTIFIER_LENGTH (attr_name); const char *s = IDENTIFIER_POINTER (attr_name); - if (l > 4 && s[0] == '_' && s[1] == '_' && s[l - 1] == '_' && s[l - 2] == '_') - return get_identifier_with_length (s + 2, l - 4); + if (canonicalize_attr_name (s, l)) + return get_identifier_with_length (s, l); return attr_name; } diff --git a/gcc/c-family/c-pragma.c b/gcc/c-family/c-pragma.c index a9be8df0384..a299ceff6a2 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); + free (args); + 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 1a5b9bfcca9..de9b848eda5 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 eee4c6737bb..6e6c580e329 100644 --- a/gcc/doc/extend.texi +++ b/gcc/doc/extend.texi @@ -23767,6 +23767,25 @@ 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 2ea23d07c4c..297ca98deae 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -8707,6 +8707,26 @@ 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 caed6255500..175b4635bb4 100644 --- a/gcc/opts.c +++ b/gcc/opts.c @@ -2611,6 +2611,26 @@ 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/testsuite/c-c++-common/Wno-attributes-3.c b/gcc/testsuite/c-c++-common/Wno-attributes-3.c new file mode 100644 index 00000000000..64370f2ef6f --- /dev/null +++ b/gcc/testsuite/c-c++-common/Wno-attributes-3.c @@ -0,0 +1,9 @@ +/* PR c++/101940 */ +/* { dg-do compile } */ +/* { dg-additional-options "-Wno-attributes=___::" } */ +/* { dg-additional-options "-Wno-attributes=c::____" } */ +/* { dg-additional-options "-Wno-attributes=____::____" } */ +/* { dg-additional-options "-Wno-attributes=c@::attr" } */ +/* { dg-additional-options "-Wno-attributes=c2::@tr" } */ + +/* { dg-error "wrong argument to ignored attributes" "" { target *-*-* } 0 } */ diff --git a/gcc/toplev.c b/gcc/toplev.c index e91f083f8ff..99276bde87d 100644 --- a/gcc/toplev.c +++ b/gcc/toplev.c @@ -457,6 +457,8 @@ 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. */