Rollup merge of rust-lang#134300 - RalfJung:remove-dead-attrs, r=chenyukang

remove long-deprecated no-op attributes no_start and crate_id

These have emitted a deprecation warning since forever (rust-lang#64471) and they already don't do anything. In fact they [apparently](rust-lang#64471 (comment)) have done nothing since pre-1.0, so... do we even need a crater run? Doesn't seem worth it.

Author: matthiaskrgr

compiler/rustc_feature/src/builtin_attrs.rs

@@ -408,11 +408,6 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
         crate_type, CrateLevel, template!(NameValueStr: "bin|lib|..."), DuplicatesOk,
         EncodeCrossCrate::No,
     ),
-    // crate_id is deprecated
-    ungated!(
-        crate_id, CrateLevel, template!(NameValueStr: "ignored"), FutureWarnFollowing,
-        EncodeCrossCrate::No,
-    ),
 
     // ABI, linking, symbols, and FFI
     ungated!(
@@ -448,7 +443,6 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
     ),
 
     // Entry point:
-    ungated!(no_start, CrateLevel, template!(Word), WarnFollowing, EncodeCrossCrate::No),
     ungated!(no_main, CrateLevel, template!(Word), WarnFollowing, EncodeCrossCrate::No),
 
     // Modules, prelude, and resolution:

compiler/rustc_lint/messages.ftl

@@ -69,12 +69,10 @@ lint_builtin_const_no_mangle = const items should never be `#[no_mangle]`
 
 lint_builtin_decl_unsafe_fn = declaration of an `unsafe` function
 lint_builtin_decl_unsafe_method = declaration of an `unsafe` method
-lint_builtin_deprecated_attr_default_suggestion = remove this attribute
 
 lint_builtin_deprecated_attr_link = use of deprecated attribute `{$name}`: {$reason}. See {$link}
     .msg_suggestion = {$msg}
     .default_suggestion = remove this attribute
-lint_builtin_deprecated_attr_used = use of deprecated attribute `{$name}`: no longer used
 lint_builtin_deref_nullptr = dereferencing a null pointer
     .label = this code causes undefined behavior when executed
 

compiler/rustc_lint/src/builtin.rs

@@ -20,7 +20,7 @@ use rustc_abi::BackendRepr;
 use rustc_ast::tokenstream::{TokenStream, TokenTree};
 use rustc_ast::visit::{FnCtxt, FnKind};
 use rustc_ast::{self as ast, *};
-use rustc_ast_pretty::pprust::{self, expr_to_string};
+use rustc_ast_pretty::pprust::expr_to_string;
 use rustc_errors::{Applicability, LintDiagnostic};
 use rustc_feature::{AttributeGate, BuiltinAttribute, GateIssue, Stability, deprecated_attributes};
 use rustc_hir as hir;
@@ -49,7 +49,7 @@ use rustc_trait_selection::traits::{self};
 use crate::errors::BuiltinEllipsisInclusiveRangePatterns;
 use crate::lints::{
     BuiltinAnonymousParams, BuiltinConstNoMangle, BuiltinDeprecatedAttrLink,
-    BuiltinDeprecatedAttrLinkSuggestion, BuiltinDeprecatedAttrUsed, BuiltinDerefNullptr,
+    BuiltinDeprecatedAttrLinkSuggestion, BuiltinDerefNullptr,
     BuiltinEllipsisInclusiveRangePatternsLint, BuiltinExplicitOutlives,
     BuiltinExplicitOutlivesSuggestion, BuiltinFeatureIssueNote, BuiltinIncompleteFeatures,
     BuiltinIncompleteFeaturesHelp, BuiltinInternalFeatures, BuiltinKeywordIdents,
@@ -848,12 +848,6 @@ impl EarlyLintPass for DeprecatedAttr {
                 return;
             }
         }
-        if attr.has_name(sym::no_start) || attr.has_name(sym::crate_id) {
-            cx.emit_span_lint(DEPRECATED, attr.span, BuiltinDeprecatedAttrUsed {
-                name: pprust::path_to_string(&attr.get_normal_item().path),
-                suggestion: attr.span,
-            });
-        }
     }
 }
 

compiler/rustc_lint/src/lints.rs

@@ -177,19 +177,6 @@ pub(crate) enum BuiltinDeprecatedAttrLinkSuggestion<'a> {
     },
 }
 
-#[derive(LintDiagnostic)]
-#[diag(lint_builtin_deprecated_attr_used)]
-pub(crate) struct BuiltinDeprecatedAttrUsed {
-    pub name: String,
-    #[suggestion(
-        lint_builtin_deprecated_attr_default_suggestion,
-        style = "short",
-        code = "",
-        applicability = "machine-applicable"
-    )]
-    pub suggestion: Span,
-}
-
 #[derive(LintDiagnostic)]
 #[diag(lint_builtin_unused_doc_comment)]
 pub(crate) struct BuiltinUnusedDocComment<'a> {

compiler/rustc_span/src/symbol.rs

@@ -707,7 +707,6 @@ symbols! {
         coverage,
         coverage_attribute,
         cr,
-        crate_id,
         crate_in_paths,
         crate_local,
         crate_name,
@@ -1390,7 +1389,6 @@ symbols! {
         no_mangle,
         no_sanitize,
         no_stack_check,
-        no_start,
         no_std,
         nomem,
         non_ascii_idents,

tests/ui/feature-gates/issue-43106-gating-of-builtin-attrs.rs

@@ -81,20 +81,11 @@
 #![crate_name = "0900"]
 #![crate_type = "bin"] // cannot pass "0800" here
 
-#![crate_id = "10"]
-//~^ WARN use of deprecated attribute
-//~| HELP remove this attribute
-//~| NOTE `#[warn(deprecated)]` on by default
-
 // FIXME(#44232) we should warn that this isn't used.
 #![feature(rust1)]
 //~^ WARN no longer requires an attribute to enable
 //~| NOTE `#[warn(stable_features)]` on by default
 
-#![no_start]
-//~^ WARN use of deprecated attribute
-//~| HELP remove this attribute
-
 // (cannot easily gating state of crate-level #[no_main]; but non crate-level is below at "0400")
 #![no_builtins]
 #![recursion_limit = "0200"]