Add lots of static Symbols.

These will be used in the subsequent commits. Many of them are
attributes.

The commit also adds the ability to handle symbols that aren't
identifiers (e.g. "proc-macro").

src/librustc_macros/src/symbols.rs

@@ -11,7 +11,7 @@ use quote::quote;
 #[allow(non_camel_case_types)]
 mod kw {
     syn::custom_keyword!(Keywords);
-    syn::custom_keyword!(Other);
+    syn::custom_keyword!(Symbols);
 }
 
 struct Keyword {
@@ -33,14 +33,24 @@ impl Parse for Keyword {
     }
 }
 
-struct Symbol(Ident);
+struct Symbol {
+    name: Ident,
+    value: Option<LitStr>,
+}
 
 impl Parse for Symbol {
     fn parse(input: ParseStream<'_>) -> Result<Self> {
-        let ident: Ident = input.parse()?;
+        let name = input.parse()?;
+        let value = match input.parse::<Token![:]>() {
+            Ok(_) => Some(input.parse()?),
+            Err(_) => None,
+        };
         input.parse::<Token![,]>()?;
 
-        Ok(Symbol(ident))
+        Ok(Symbol {
+            name,
+            value,
+        })
     }
 }
 
@@ -69,7 +79,7 @@ impl Parse for Input {
         braced!(content in input);
         let keywords = content.parse()?;
 
-        input.parse::<kw::Other>()?;
+        input.parse::<kw::Symbols>()?;
         let content;
         braced!(content in input);
         let symbols = content.parse()?;
@@ -116,19 +126,22 @@ pub fn symbols(input: TokenStream) -> TokenStream {
     }
 
     for symbol in &input.symbols.0 {
-        let value = &symbol.0;
+        let name = &symbol.name;
-        let value_str = value.to_string();
+        let value = match &symbol.value {
-        check_dup(&value_str);
+            Some(value) => value.value(),
+            None => name.to_string(),
+        };
+        check_dup(&value);
         prefill_stream.extend(quote! {
-            #value_str,
+            #value,
         });
         symbols_stream.extend(quote! {
-            pub const #value: Symbol = Symbol::new(#counter);
+            pub const #name: Symbol = Symbol::new(#counter);
         });
         counter += 1;
     }
 
-    TokenStream::from(quote! {
+    let tt = TokenStream::from(quote! {
         macro_rules! keywords {
             () => {
                 #keyword_stream
@@ -159,5 +172,11 @@ pub fn symbols(input: TokenStream) -> TokenStream {
                 ])
             }
         }
-    })
+    });
+
+    // To see the generated code generated, uncomment this line, recompile, and
+    // run the resulting output through `rustfmt`.
+    //eprintln!("{}", tt);
+
+    tt
 }

src/libsyntax_pos/symbol.rs

@@ -99,88 +99,375 @@ symbols! {
         Union:              "union",
     }
 
-    // Other symbols that can be referred to with syntax_pos::symbols::*
+    // Symbols that can be referred to with syntax_pos::symbols::*. The symbol
-    Other {
+    // is the stringified identifier unless otherwise specified (e.g.
+    // `proc_dash_macro` represents "proc-macro").
+    Symbols {
+        aarch64_target_feature,
+        abi,
+        abi_amdgpu_kernel,
+        abi_msp430_interrupt,
+        abi_ptx,
+        abi_sysv64,
+        abi_thiscall,
+        abi_unadjusted,
+        abi_vectorcall,
+        abi_x86_interrupt,
+        aborts,
+        advanced_slice_patterns,
+        adx_target_feature,
         alias,
         align,
+        alignstack,
+        all,
+        allocator,
+        allocator_internals,
         alloc_error_handler,
         allow,
+        allowed,
         allow_fail,
         allow_internal_unsafe,
         allow_internal_unstable,
+        allow_internal_unstable_backcompat_hack,
+        always,
+        any,
+        arbitrary_self_types,
+        arm_target_feature,
+        asm,
+        associated_consts,
+        associated_type_defaults,
+        associated_types,
+        async_await,
+        attr,
+        attributes,
+        attr_literals,
+        augmented_assignments,
         automatically_derived,
+        avx512_target_feature,
+        await_macro,
+        bin,
+        bind_by_move_pattern_guards,
+        block,
+        borrowck_graphviz_postflow,
+        borrowck_graphviz_preflow,
+        box_patterns,
+        box_syntax,
+        braced_empty_structs,
+        C,
+        cdylib,
         cfg,
         cfg_attr,
+        cfg_attr_multi,
+        cfg_target_feature,
+        cfg_target_has_atomic,
+        cfg_target_thread_local,
+        cfg_target_vendor,
+        clone,
+        clone_closures,
+        clone_from,
+        closure_to_fn_coercion,
+        cmpxchg16b_target_feature,
         cold,
+        compile_error,
         compiler_builtins,
+        concat_idents,
+        conservative_impl_trait,
+        console,
+        const_compare_raw_pointers,
+        const_fn,
+        const_fn_union,
+        const_generics,
+        const_indexing,
+        const_let,
+        const_panic,
+        const_raw_ptr_deref,
+        const_raw_ptr_to_usize_cast,
+        const_transmute,
+        contents,
+        convert,
+        copy_closures,
+        core,
+        core_intrinsics,
         crate_id,
+        crate_in_paths,
         crate_name,
         crate_type,
+        crate_visibility_modifier,
+        custom_attribute,
+        custom_derive,
+        custom_inner_attributes,
+        custom_test_frameworks,
+        c_variadic,
+        decl_macro,
         default_lib_allocator,
+        default_type_parameter_fallback,
+        default_type_params,
         deny,
         deprecated,
         derive,
         doc,
+        doc_alias,
+        doc_cfg,
+        doc_keyword,
+        doc_masked,
+        doc_spotlight,
+        document_private_items,
+        dotdoteq_in_patterns,
+        dotdot_in_tuple_patterns,
+        dropck_eyepatch,
+        dropck_parametricity,
+        drop_types_in_const,
+        dylib,
+        dyn_trait,
+        eh_personality,
+        eh_unwind_resume,
+        enable,
+        Err,
+        except,
+        exclusive_range_pattern,
+        exhaustive_integer_patterns,
+        exhaustive_patterns,
+        existential_type,
+        expected,
         export_name,
+        extern_absolute_paths,
+        external_doc,
+        extern_crate_item_prelude,
+        extern_crate_self,
+        extern_in_paths,
+        extern_prelude,
+        extern_types,
+        f16c_target_feature,
         feature,
         ffi_returns_twice,
+        field_init_shorthand,
+        file,
+        fn_must_use,
         forbid,
+        format_args_nl,
+        from,
+        From,
+        from_error,
+        from_generator,
+        from_ok,
         fundamental,
+        future,
+        Future,
+        generators,
+        generic_associated_types,
+        generic_param_attrs,
         global_allocator,
+        global_asm,
+        globs,
+        hexagon_target_feature,
+        hidden,
+        homogeneous_aggregate,
+        html_favicon_url,
+        html_logo_url,
+        html_no_source,
+        html_playground_url,
+        html_root_url,
+        i128,
+        i128_type,
+        i16,
+        i32,
+        i64,
+        i8,
+        ident,
+        if_let,
+        if_while_or_patterns,
         ignore,
+        impl_header_lifetime_elision,
+        impl_trait_in_bindings,
+        import_shadowing,
+        in_band_lifetimes,
         include,
+        inclusive_range_syntax,
+        infer_outlives_requirements,
+        infer_static_outlives_requirements,
         inline,
+        intel,
+        into_iter,
+        IntoIterator,
+        into_result,
+        intrinsics,
+        irrefutable_let_patterns,
+        isize,
+        issue,
+        issue_5723_bootstrap,
+        issue_tracker_base_url,
+        item_like_imports,
+        iter,
+        Iterator,
         keyword,
+        kind,
+        label,
+        label_break_value,
         lang,
+        lang_items,
+        lib,
         link,
+        linkage,
         link_args,
+        link_cfg,
+        link_llvm_intrinsics,
         link_name,
         link_section,
-        linkage,
+        lint_reasons,
+        local_inner_macros,
+        log_syntax,
+        loop_break_value,
+        macro_at_most_once_rep,
         macro_escape,
         macro_export,
+        macro_lifetime_matcher,
+        macro_literal_matcher,
+        macro_reexport,
+        macro_rules,
+        macros_in_extern,
         macro_use,
+        macro_vis_matcher,
         main,
+        managed_boxes,
         marker,
+        marker_trait_attr,
         masked,
+        match_beginning_vert,
+        match_default_bindings,
         may_dangle,
+        message,
+        min_const_fn,
+        min_const_unsafe_fn,
+        mips_target_feature,
+        mmx_target_feature,
+        module,
+        more_struct_aliases,
+        movbe_target_feature,
         must_use,
         naked,
+        naked_functions,
+        name,
         needs_allocator,
         needs_panic_runtime,
+        negate_unsigned,
+        never,
+        never_type,
+        next,
+        nll,
         no_builtins,
         no_core,
+        no_crate_inject,
         no_debug,
+        no_default_passes,
         no_implicit_prelude,
+        no_inline,
         no_link,
         no_main,
         no_mangle,
+        non_ascii_idents,
+        None,
+        non_exhaustive,
+        non_modrs_mods,
+        no_stack_check,
         no_start,
         no_std,
-        non_exhaustive,
+        not,
+        note,
+        Ok,
         omit_gdb_pretty_printer_section,
+        on,
+        on_unimplemented,
+        oom,
+        ops,
         optimize,
+        optimize_attribute,
+        optin_builtin_traits,
+        option,
+        Option,
+        opt_out_copy,
+        overlapping_marker_traits,
+        packed,
         panic_handler,
+        panic_impl,
+        panic_implementation,
         panic_runtime,
+        passes,
         path,
+        pattern_parentheses,
+        Pending,
+        pin,
+        Pin,
+        platform_intrinsics,
         plugin,
         plugin_registrar,
+        plugins,
+        Poll,
+        poll_with_tls_context,
+        powerpc_target_feature,
+        precise_pointer_size_matching,
+        prelude,
         prelude_import,
+        primitive,
+        proc_dash_macro: "proc-macro",
         proc_macro,
         proc_macro_attribute,
         proc_macro_derive,
+        proc_macro_expr,
+        proc_macro_gen,
+        proc_macro_hygiene,
+        proc_macro_mod,
+        proc_macro_non_items,
+        proc_macro_path_invoc,
         profiler_runtime,
+        pub_restricted,
+        pushpop_unsafe,
+        quad_precision_float,
+        question_mark,
+        quote,
+        Range,
+        RangeFrom,
+        RangeFull,
+        RangeInclusive,
+        RangeTo,
+        RangeToInclusive,
+        raw_identifiers,
+        Ready,
+        reason,
         recursion_limit,
         reexport_test_harness_main,
+        reflect,
+        relaxed_adts,
         repr,
+        repr128,
+        repr_align,
+        repr_align_enum,
+        repr_packed,
+        repr_simd,
+        repr_transparent,
+        re_rebalance_coherence,
+        result,
+        Result,
+        Return,
+        rlib,
+        rtm_target_feature,
+        rust,
+        rust_2015_preview,
+        rust_2018_preview,
+        rust_begin_unwind,
+        rustc_allocator_nounwind,
+        rustc_allow_const_fn_ptr,
         rustc_args_required_const,
+        rustc_attrs,
         rustc_clean,
         rustc_const_unstable,
         rustc_conversion_suggestion,
         rustc_copy_clone_marker,
         rustc_def_path,
         rustc_deprecated,
+        rustc_diagnostic_macros,
         rustc_dirty,
+        rustc_doc_only_macro,
+        rustc_dump_env_program_clauses,
         rustc_dump_program_clauses,
         rustc_dump_user_substs,
         rustc_error,
@@ -191,13 +478,21 @@ symbols! {
         rustc_layout_scalar_valid_range_end,
         rustc_layout_scalar_valid_range_start,
         rustc_mir,
+        rustc_object_lifetime_default,
         rustc_on_unimplemented,
         rustc_outlives,
         rustc_paren_sugar,
         rustc_partition_codegened,
         rustc_partition_reused,
+        rustc_peek,
+        rustc_peek_definite_init,
+        rustc_peek_maybe_init,
+        rustc_peek_maybe_uninit,
+        rustc_private,
         rustc_proc_macro_decls,
+        rustc_promotable,
         rustc_regions,
+        rustc_stable,
         rustc_std_internal_symbol,
         rustc_symbol_name,
         rustc_synthetic,
@@ -205,23 +500,108 @@ symbols! {
         rustc_then_this_would_need,
         rustc_transparent_macro,
         rustc_variance,
+        rustdoc,
+        rust_eh_personality,
+        rust_eh_unwind_resume,
+        rust_oom,
+        __rust_unstable_column,
+        rvalue_static_promotion,
         sanitizer_runtime,
+        self_in_typedefs,
+        self_struct_ctor,
+        Send,
         should_panic,
         simd,
+        simd_ffi,
+        since,
+        size,
+        slice_patterns,
+        slicing_syntax,
+        Some,
+        specialization,
+        speed,
         spotlight,
+        sse4a_target_feature,
         stable,
+        staged_api,
         start,
+        static_in_const,
+        staticlib,
+        static_nobundle,
+        static_recursion,
+        std,
+        stmt_expr_attributes,
+        stop_after_dataflow,
+        struct_field_attributes,
+        struct_inherit,
         structural_match,
+        struct_variant,
+        suggestion,
         target_feature,
+        target_has_atomic,
+        target_thread_local,
+        task,
+        tbm_target_feature,
+        termination_trait,
+        termination_trait_test,
+        test,
+        test_2018_feature,
+        test_accepted_feature,
+        test_removed_feature,
         test_runner,
         thread_local,
+        tool_attributes,
+        tool_lints,
+        trace_macros,
+        trait_alias,
+        transmute,
+        transparent,
+        trivial_bounds,
+        Try,
+        try_blocks,
+        tuple_indexing,
+        ty,
+        type_alias_enum_variants,
+        type_ascription,
         type_length_limit,
+        type_macros,
+        u128,
+        u16,
+        u32,
+        u64,
+        u8,
+        unboxed_closures,
+        underscore_const_names,
+        underscore_imports,
+        underscore_lifetimes,
+        uniform_paths,
+        universal_impl_trait,
+        unmarked_api,
+        unrestricted_attribute_tokens,
         unsafe_destructor_blind_to_params,
+        unsafe_no_drop_flag,
+        unsized_locals,
+        unsized_tuple_coercion,
         unstable,
+        untagged_unions,
         unwind,
+        unwind_attributes,
         used,
+        use_extern_macros,
+        use_nested_groups,
+        usize,
+        v1,
+        vis,
+        visible_private_types,
+        volatile,
         warn,
+        warn_directory_ownership,
+        wasm_import_module,
+        wasm_target_feature,
+        while_let,
+        windows,
         windows_subsystem,
+        Yield,
     }
 }