Merging upstream version 1.71.1+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

24 files changed, 463 insertions, 251 deletions

diff --git a/compiler/rustc_builtin_macros/Cargo.toml b/compiler/rustc_builtin_macros/Cargo.toml
index 336e14ef9..44012e802 100644
--- a/compiler/rustc_builtin_macros/Cargo.toml
+++ b/compiler/rustc_builtin_macros/Cargo.toml
@@ -14,9 +14,11 @@ rustc_data_structures = { path = "../rustc_data_structures" }
 rustc_errors = { path = "../rustc_errors" }
 rustc_expand = { path = "../rustc_expand" }
 rustc_feature = { path = "../rustc_feature" }
+rustc_index = { path = "../rustc_index" }
 rustc_lexer = { path = "../rustc_lexer" }
 rustc_lint_defs = { path = "../rustc_lint_defs" }
 rustc_macros = { path = "../rustc_macros" }
+rustc_fluent_macro = { path = "../rustc_fluent_macro" }
 rustc_parse_format = { path = "../rustc_parse_format" }
 rustc_parse = { path = "../rustc_parse" }
 rustc_session = { path = "../rustc_session" }
diff --git a/compiler/rustc_builtin_macros/messages.ftl b/compiler/rustc_builtin_macros/messages.ftl
index 83dc1ac50..f00cd39cb 100644
--- a/compiler/rustc_builtin_macros/messages.ftl
+++ b/compiler/rustc_builtin_macros/messages.ftl
@@ -1,10 +1,50 @@
-builtin_macros_requires_cfg_pattern =
-    macro requires a cfg-pattern as an argument
-    .label = cfg-pattern required
+builtin_macros_alloc_error_must_be_fn = alloc_error_handler must be a function
 
-builtin_macros_expected_one_cfg_pattern = expected 1 cfg-pattern
+builtin_macros_asm_clobber_abi = clobber_abi
+builtin_macros_asm_clobber_no_reg = asm with `clobber_abi` must specify explicit registers for outputs
+builtin_macros_asm_clobber_outputs = generic outputs
 
-builtin_macros_alloc_error_must_be_fn = alloc_error_handler must be a function
+builtin_macros_asm_duplicate_arg = duplicate argument named `{$name}`
+    .label = previously here
+    .arg = duplicate argument
+
+builtin_macros_asm_expected_comma = expected token: `,`
+    .label = expected `,`
+
+builtin_macros_asm_expected_other = expected operand, {$is_global_asm ->
+    [true] options
+    *[false] clobber_abi, options
+    }, or additional template string
+
+builtin_macros_asm_explicit_register_name = explicit register arguments cannot have names
+
+builtin_macros_asm_modifier_invalid = asm template modifier must be a single character
+
+builtin_macros_asm_mutually_exclusive = the `{$opt1}` and `{$opt2}` options are mutually exclusive
+
+builtin_macros_asm_noreturn = asm outputs are not allowed with the `noreturn` option
+
+builtin_macros_asm_opt_already_provided = the `{$symbol}` option was already provided
+    .label = this option was already provided
+    .suggestion = remove this option
+
+builtin_macros_asm_pos_after = positional arguments cannot follow named arguments or explicit register arguments
+    .pos = positional argument
+    .named = named argument
+    .explicit = explicit register argument
+
+builtin_macros_asm_pure_combine = the `pure` option must be combined with either `nomem` or `readonly`
+
+builtin_macros_asm_pure_no_output = asm with the `pure` option must have at least one output
+
+builtin_macros_asm_requires_template = requires at least a template string argument
+
+builtin_macros_asm_sym_no_path = expected a path for argument to `sym`
+
+builtin_macros_asm_underscore_input = _ cannot be used for input operands
+
+builtin_macros_assert_missing_comma = unexpected string literal
+    .suggestion = try adding a comma
 
 builtin_macros_assert_requires_boolean = macro requires a boolean expression as an argument
     .label = boolean expression required
@@ -12,51 +52,50 @@ builtin_macros_assert_requires_boolean = macro requires a boolean expression as
 builtin_macros_assert_requires_expression = macro requires an expression as an argument
     .suggestion = try removing semicolon
 
-builtin_macros_assert_missing_comma = unexpected string literal
-    .suggestion = try adding a comma
+builtin_macros_bad_derive_target = `derive` may only be applied to `struct`s, `enum`s and `union`s
+    .label = not applicable here
+    .label2 = not a `struct`, `enum` or `union`
+
+builtin_macros_cannot_derive_union = this trait cannot be derived for unions
 
-builtin_macros_cfg_accessible_unspecified_path = `cfg_accessible` path is not specified
-builtin_macros_cfg_accessible_multiple_paths = multiple `cfg_accessible` paths are specified
-builtin_macros_cfg_accessible_literal_path = `cfg_accessible` path cannot be a literal
 builtin_macros_cfg_accessible_has_args = `cfg_accessible` path cannot accept arguments
 
 builtin_macros_cfg_accessible_indeterminate = cannot determine whether the path is accessible or not
 
-builtin_macros_concat_bytestr = cannot concatenate a byte string literal
-
-builtin_macros_concat_missing_literal = expected a literal
-    .note = only literals (like `"foo"`, `-42` and `3.14`) can be passed to `concat!()`
+builtin_macros_cfg_accessible_literal_path = `cfg_accessible` path cannot be a literal
+builtin_macros_cfg_accessible_multiple_paths = multiple `cfg_accessible` paths are specified
+builtin_macros_cfg_accessible_unspecified_path = `cfg_accessible` path is not specified
+builtin_macros_concat_bytes_array = cannot concatenate doubly nested array
+    .note = byte strings are treated as arrays of bytes
+    .help = try flattening the array
 
-builtin_macros_concat_bytes_missing_literal = expected a byte literal
-    .note = only byte literals (like `b"foo"`, `b's'` and `[3, 4, 5]`) can be passed to `concat_bytes!()`
+builtin_macros_concat_bytes_bad_repeat = repeat count is not a positive number
 
 builtin_macros_concat_bytes_invalid = cannot concatenate {$lit_kind} literals
     .byte_char = try using a byte character
     .byte_str = try using a byte string
     .number_array = try wrapping the number in an array
 
-builtin_macros_concat_bytes_oob = numeric literal is out of bounds
+builtin_macros_concat_bytes_missing_literal = expected a byte literal
+    .note = only byte literals (like `b"foo"`, `b's'` and `[3, 4, 5]`) can be passed to `concat_bytes!()`
 
 builtin_macros_concat_bytes_non_u8 = numeric literal is not a `u8`
 
-builtin_macros_concat_bytes_array = cannot concatenate doubly nested array
-    .note = byte strings are treated as arrays of bytes
-    .help = try flattening the array
+builtin_macros_concat_bytes_oob = numeric literal is out of bounds
 
-builtin_macros_concat_bytes_bad_repeat = repeat count is not a positive number
+builtin_macros_concat_bytestr = cannot concatenate a byte string literal
+
+builtin_macros_concat_idents_ident_args = `concat_idents!()` requires ident args
 
 builtin_macros_concat_idents_missing_args = `concat_idents!()` takes 1 or more arguments
 builtin_macros_concat_idents_missing_comma = `concat_idents!()` expecting comma
-builtin_macros_concat_idents_ident_args = `concat_idents!()` requires ident args
+builtin_macros_concat_missing_literal = expected a literal
+    .note = only literals (like `"foo"`, `-42` and `3.14`) can be passed to `concat!()`
 
-builtin_macros_bad_derive_target = `derive` may only be applied to `struct`s, `enum`s and `union`s
-    .label = not applicable here
-    .label2 = not a `struct`, `enum` or `union`
+builtin_macros_default_arg = `#[default]` attribute does not accept a value
+    .suggestion = try using `#[default]`
 
-builtin_macros_unexpected_lit = expected path to a trait, found literal
-    .label = not a trait
-    .str_lit = try using `#[derive({$sym})]`
-    .other = for example, write `#[derive(Debug)]` for `Debug`
+builtin_macros_derive_macro_call = `derive` cannot be used on items with type macros
 
 builtin_macros_derive_path_args_list = traits in `#[derive(...)]` don't accept arguments
     .suggestion = remove the arguments
@@ -64,66 +103,38 @@ builtin_macros_derive_path_args_list = traits in `#[derive(...)]` don't accept a
 builtin_macros_derive_path_args_value = traits in `#[derive(...)]` don't accept values
     .suggestion = remove the value
 
-builtin_macros_derive_macro_call = `derive` cannot be used on items with type macros
-
-builtin_macros_cannot_derive_union = this trait cannot be derived for unions
-
-builtin_macros_no_default_variant = no default declared
-    .help = make a unit variant default by placing `#[default]` above it
-    .suggestion = make `{$ident}` default
-
-builtin_macros_multiple_defaults = multiple declared defaults
-    .label = first default
-    .additional = additional default
-    .note = only one variant can be default
-    .suggestion = make `{$ident}` default
-
-builtin_macros_non_unit_default = the `#[default]` attribute may only be used on unit enum variants
-    .help = consider a manual implementation of `Default`
-
-builtin_macros_non_exhaustive_default = default variant must be exhaustive
-    .label = declared `#[non_exhaustive]` here
-    .help = consider a manual implementation of `Default`
-
-builtin_macros_multiple_default_attrs = multiple `#[default]` attributes
-    .note = only one `#[default]` attribute is needed
-    .label = `#[default]` used here
-    .label_again = `#[default]` used again here
-    .help = try removing {$only_one ->
-    [true] this
-    *[false] these
-    }
-
-builtin_macros_default_arg = `#[default]` attribute does not accept a value
-    .suggestion = try using `#[default]`
-
-builtin_macros_env_takes_args = `env!()` takes 1 or 2 arguments
-
 builtin_macros_env_not_defined = environment variable `{$var}` not defined at compile time
     .cargo = Cargo sets build script variables at run time. Use `std::env::var("{$var}")` instead
     .other = use `std::env::var("{$var}")` to read the variable at run time
 
-builtin_macros_format_requires_string = requires at least a format string argument
+builtin_macros_env_takes_args = `env!()` takes 1 or 2 arguments
+
+builtin_macros_expected_one_cfg_pattern = expected 1 cfg-pattern
 
 builtin_macros_format_duplicate_arg = duplicate argument named `{$ident}`
     .label1 = previously here
     .label2 = duplicate argument
 
+builtin_macros_format_no_arg_named = there is no argument named `{$name}`
+    .note = did you intend to capture a variable `{$name}` from the surrounding scope?
+    .note2 = to avoid ambiguity, `format_args!` cannot capture variables when the format string is expanded from a macro
+
+builtin_macros_format_pos_mismatch = {$n} positional {$n ->
+    [one] argument
+    *[more] arguments
+    } in format string, but {$desc}
+
 builtin_macros_format_positional_after_named = positional arguments cannot follow named arguments
     .label = positional arguments must be before named arguments
     .named_args = named argument
 
+builtin_macros_format_requires_string = requires at least a format string argument
+
 builtin_macros_format_string_invalid = invalid format string: {$desc}
     .label = {$label1} in format string
     .note = {$note}
     .second_label = {$label}
 
-builtin_macros_sugg = consider using a positional formatting argument instead
-
-builtin_macros_format_no_arg_named = there is no argument named `{$name}`
-    .note = did you intend to capture a variable `{$name}` from the surrounding scope?
-    .note2 = to avoid ambiguity, `format_args!` cannot capture variables when the format string is expanded from a macro
-
 builtin_macros_format_unknown_trait = unknown format trait `{$ty}`
     .note = the only appropriate formatting traits are:
                                             - ``, which uses the `Display` trait
@@ -145,7 +156,49 @@ builtin_macros_format_unused_arg = {$named ->
 builtin_macros_format_unused_args = multiple unused formatting arguments
     .label = multiple missing formatting specifiers
 
-builtin_macros_format_pos_mismatch = {$n} positional {$n ->
-    [one] argument
-    *[more] arguments
-    } in format string, but {$desc}
+builtin_macros_global_asm_clobber_abi = `clobber_abi` cannot be used with `global_asm!`
+
+builtin_macros_multiple_default_attrs = multiple `#[default]` attributes
+    .note = only one `#[default]` attribute is needed
+    .label = `#[default]` used here
+    .label_again = `#[default]` used again here
+    .help = try removing {$only_one ->
+    [true] this
+    *[false] these
+    }
+
+builtin_macros_multiple_defaults = multiple declared defaults
+    .label = first default
+    .additional = additional default
+    .note = only one variant can be default
+    .suggestion = make `{$ident}` default
+
+builtin_macros_no_default_variant = no default declared
+    .help = make a unit variant default by placing `#[default]` above it
+    .suggestion = make `{$ident}` default
+
+builtin_macros_non_exhaustive_default = default variant must be exhaustive
+    .label = declared `#[non_exhaustive]` here
+    .help = consider a manual implementation of `Default`
+
+builtin_macros_non_unit_default = the `#[default]` attribute may only be used on unit enum variants
+    .help = consider a manual implementation of `Default`
+
+builtin_macros_requires_cfg_pattern =
+    macro requires a cfg-pattern as an argument
+    .label = cfg-pattern required
+
+builtin_macros_sugg = consider using a positional formatting argument instead
+
+builtin_macros_test_bad_fn = {$kind} functions cannot be used for tests
+    .label = `{$kind}` because of this
+
+builtin_macros_test_case_non_item = `#[test_case]` attribute is only allowed on items
+
+builtin_macros_test_runner_invalid = `test_runner` argument must be a path
+builtin_macros_test_runner_nargs = `#![test_runner(..)]` accepts exactly 1 argument
+
+builtin_macros_unexpected_lit = expected path to a trait, found literal
+    .label = not a trait
+    .str_lit = try using `#[derive({$sym})]`
+    .other = for example, write `#[derive(Debug)]` for `Debug`
diff --git a/compiler/rustc_builtin_macros/src/asm.rs b/compiler/rustc_builtin_macros/src/asm.rs
index 8c1579baa..5217e317a 100644
--- a/compiler/rustc_builtin_macros/src/asm.rs
+++ b/compiler/rustc_builtin_macros/src/asm.rs
@@ -2,9 +2,10 @@ use rustc_ast as ast;
 use rustc_ast::ptr::P;
 use rustc_ast::token::{self, Delimiter};
 use rustc_ast::tokenstream::TokenStream;
-use rustc_data_structures::fx::{FxHashMap, FxHashSet};
-use rustc_errors::{Applicability, PResult};
+use rustc_data_structures::fx::{FxHashMap, FxIndexMap};
+use rustc_errors::PResult;
 use rustc_expand::base::{self, *};
+use rustc_index::bit_set::GrowableBitSet;
 use rustc_parse::parser::Parser;
 use rustc_parse_format as parse;
 use rustc_session::lint;
@@ -15,11 +16,13 @@ use rustc_span::{InnerSpan, Span};
 use rustc_target::asm::InlineAsmArch;
 use smallvec::smallvec;
 
+use crate::errors;
+
 pub struct AsmArgs {
     pub templates: Vec<P<ast::Expr>>,
     pub operands: Vec<(ast::InlineAsmOperand, Span)>,
-    named_args: FxHashMap<Symbol, usize>,
-    reg_args: FxHashSet<usize>,
+    named_args: FxIndexMap<Symbol, usize>,
+    reg_args: GrowableBitSet<usize>,
     pub clobber_abis: Vec<(Symbol, Span)>,
     options: ast::InlineAsmOptions,
     pub options_spans: Vec<Span>,
@@ -47,15 +50,15 @@ pub fn parse_asm_args<'a>(
     let diag = &sess.span_diagnostic;
 
     if p.token == token::Eof {
-        return Err(diag.struct_span_err(sp, "requires at least a template string argument"));
+        return Err(diag.create_err(errors::AsmRequiresTemplate { span: sp }));
     }
 
     let first_template = p.parse_expr()?;
     let mut args = AsmArgs {
         templates: vec![first_template],
         operands: vec![],
-        named_args: FxHashMap::default(),
-        reg_args: FxHashSet::default(),
+        named_args: Default::default(),
+        reg_args: Default::default(),
         clobber_abis: Vec::new(),
         options: ast::InlineAsmOptions::empty(),
         options_spans: vec![],
@@ -66,10 +69,7 @@ pub fn parse_asm_args<'a>(
         if !p.eat(&token::Comma) {
             if allow_templates {
                 // After a template string, we always expect *only* a comma...
-                let mut err = diag.struct_span_err(p.token.span, "expected token: `,`");
-                err.span_label(p.token.span, "expected `,`");
-                p.maybe_annotate_with_ascription(&mut err, false);
-                return Err(err);
+                return Err(diag.create_err(errors::AsmExpectedComma { span: p.token.span }));
             } else {
                 // ...after that delegate to `expect` to also include the other expected tokens.
                 return Err(p.expect(&token::Comma).err().unwrap());
@@ -110,7 +110,7 @@ pub fn parse_asm_args<'a>(
         let op = if !is_global_asm && p.eat_keyword(kw::In) {
             let reg = parse_reg(p, &mut explicit_reg)?;
             if p.eat_keyword(kw::Underscore) {
-                let err = diag.struct_span_err(p.token.span, "_ cannot be used for input operands");
+                let err = diag.create_err(errors::AsmUnderscoreInput { span: p.token.span });
                 return Err(err);
             }
             let expr = p.parse_expr()?;
@@ -126,7 +126,7 @@ pub fn parse_asm_args<'a>(
         } else if !is_global_asm && p.eat_keyword(sym::inout) {
             let reg = parse_reg(p, &mut explicit_reg)?;
             if p.eat_keyword(kw::Underscore) {
-                let err = diag.struct_span_err(p.token.span, "_ cannot be used for input operands");
+                let err = diag.create_err(errors::AsmUnderscoreInput { span: p.token.span });
                 return Err(err);
             }
             let expr = p.parse_expr()?;
@@ -140,7 +140,7 @@ pub fn parse_asm_args<'a>(
         } else if !is_global_asm && p.eat_keyword(sym::inlateout) {
             let reg = parse_reg(p, &mut explicit_reg)?;
             if p.eat_keyword(kw::Underscore) {
-                let err = diag.struct_span_err(p.token.span, "_ cannot be used for input operands");
+                let err = diag.create_err(errors::AsmUnderscoreInput { span: p.token.span });
                 return Err(err);
             }
             let expr = p.parse_expr()?;
@@ -158,7 +158,7 @@ pub fn parse_asm_args<'a>(
             let expr = p.parse_expr()?;
             let ast::ExprKind::Path(qself, path) = &expr.kind else {
                 let err = diag
-                    .struct_span_err(expr.span, "expected a path for argument to `sym`");
+                    .create_err(errors::AsmSymNoPath { span: expr.span });
                 return Err(err);
             };
             let sym = ast::InlineAsmSym {
@@ -179,13 +179,10 @@ pub fn parse_asm_args<'a>(
                     ) => {}
                 ast::ExprKind::MacCall(..) => {}
                 _ => {
-                    let errstr = if is_global_asm {
-                        "expected operand, options, or additional template string"
-                    } else {
-                        "expected operand, clobber_abi, options, or additional template string"
-                    };
-                    let mut err = diag.struct_span_err(template.span, errstr);
-                    err.span_label(template.span, errstr);
+                    let err = diag.create_err(errors::AsmExpectedOther {
+                        span: template.span,
+                        is_global_asm,
+                    });
                     return Err(err);
                 }
             }
@@ -205,33 +202,21 @@ pub fn parse_asm_args<'a>(
         // of the argument available.
         if explicit_reg {
             if name.is_some() {
-                diag.struct_span_err(span, "explicit register arguments cannot have names").emit();
+                diag.emit_err(errors::AsmExplicitRegisterName { span });
             }
             args.reg_args.insert(slot);
         } else if let Some(name) = name {
             if let Some(&prev) = args.named_args.get(&name) {
-                diag.struct_span_err(span, &format!("duplicate argument named `{}`", name))
-                    .span_label(args.operands[prev].1, "previously here")
-                    .span_label(span, "duplicate argument")
-                    .emit();
+                diag.emit_err(errors::AsmDuplicateArg { span, name, prev: args.operands[prev].1 });
                 continue;
             }
             args.named_args.insert(name, slot);
         } else {
             if !args.named_args.is_empty() || !args.reg_args.is_empty() {
-                let mut err = diag.struct_span_err(
-                    span,
-                    "positional arguments cannot follow named arguments \
-                     or explicit register arguments",
-                );
-                err.span_label(span, "positional argument");
-                for pos in args.named_args.values() {
-                    err.span_label(args.operands[*pos].1, "named argument");
-                }
-                for pos in &args.reg_args {
-                    err.span_label(args.operands[*pos].1, "explicit register argument");
-                }
-                err.emit();
+                let named = args.named_args.values().map(|p| args.operands[*p].1).collect();
+                let explicit = args.reg_args.iter().map(|p| args.operands[p].1).collect();
+
+                diag.emit_err(errors::AsmPositionalAfter { span, named, explicit });
             }
         }
     }
@@ -240,25 +225,19 @@ pub fn parse_asm_args<'a>(
         && args.options.contains(ast::InlineAsmOptions::READONLY)
     {
         let spans = args.options_spans.clone();
-        diag.struct_span_err(spans, "the `nomem` and `readonly` options are mutually exclusive")
-            .emit();
+        diag.emit_err(errors::AsmMutuallyExclusive { spans, opt1: "nomem", opt2: "readonly" });
     }
     if args.options.contains(ast::InlineAsmOptions::PURE)
         && args.options.contains(ast::InlineAsmOptions::NORETURN)
     {
         let spans = args.options_spans.clone();
-        diag.struct_span_err(spans, "the `pure` and `noreturn` options are mutually exclusive")
-            .emit();
+        diag.emit_err(errors::AsmMutuallyExclusive { spans, opt1: "pure", opt2: "noreturn" });
     }
     if args.options.contains(ast::InlineAsmOptions::PURE)
         && !args.options.intersects(ast::InlineAsmOptions::NOMEM | ast::InlineAsmOptions::READONLY)
     {
         let spans = args.options_spans.clone();
-        diag.struct_span_err(
-            spans,
-            "the `pure` option must be combined with either `nomem` or `readonly`",
-        )
-        .emit();
+        diag.emit_err(errors::AsmPureCombine { spans });
     }
 
     let mut have_real_output = false;
@@ -285,41 +264,28 @@ pub fn parse_asm_args<'a>(
         }
     }
     if args.options.contains(ast::InlineAsmOptions::PURE) && !have_real_output {
-        diag.struct_span_err(
-            args.options_spans.clone(),
-            "asm with the `pure` option must have at least one output",
-        )
-        .emit();
+        diag.emit_err(errors::AsmPureNoOutput { spans: args.options_spans.clone() });
     }
     if args.options.contains(ast::InlineAsmOptions::NORETURN) && !outputs_sp.is_empty() {
-        let err = diag
-            .struct_span_err(outputs_sp, "asm outputs are not allowed with the `noreturn` option");
-
+        let err = diag.create_err(errors::AsmNoReturn { outputs_sp });
         // Bail out now since this is likely to confuse MIR
         return Err(err);
     }
 
     if args.clobber_abis.len() > 0 {
         if is_global_asm {
-            let err = diag.struct_span_err(
-                args.clobber_abis.iter().map(|(_, span)| *span).collect::<Vec<Span>>(),
-                "`clobber_abi` cannot be used with `global_asm!`",
-            );
+            let err = diag.create_err(errors::GlobalAsmClobberAbi {
+                spans: args.clobber_abis.iter().map(|(_, span)| *span).collect(),
+            });
 
             // Bail out now since this is likely to confuse later stages
             return Err(err);
         }
         if !regclass_outputs.is_empty() {
-            diag.struct_span_err(
-                regclass_outputs.clone(),
-                "asm with `clobber_abi` must specify explicit registers for outputs",
-            )
-            .span_labels(
-                args.clobber_abis.iter().map(|(_, span)| *span).collect::<Vec<Span>>(),
-                "clobber_abi",
-            )
-            .span_labels(regclass_outputs, "generic outputs")
-            .emit();
+            diag.emit_err(errors::AsmClobberNoReg {
+                spans: regclass_outputs,
+                clobbers: args.clobber_abis.iter().map(|(_, span)| *span).collect(),
+            });
         }
     }
 
@@ -331,25 +297,9 @@ pub fn parse_asm_args<'a>(
 /// This function must be called immediately after the option token is parsed.
 /// Otherwise, the suggestion will be incorrect.
 fn err_duplicate_option(p: &mut Parser<'_>, symbol: Symbol, span: Span) {
-    let mut err = p
-        .sess
-        .span_diagnostic
-        .struct_span_err(span, &format!("the `{}` option was already provided", symbol));
-    err.span_label(span, "this option was already provided");
-
     // Tool-only output
-    let mut full_span = span;
-    if p.token.kind == token::Comma {
-        full_span = full_span.to(p.token.span);
-    }
-    err.tool_only_span_suggestion(
-        full_span,
-        "remove this option",
-        "",
-        Applicability::MachineApplicable,
-    );
-
-    err.emit();
+    let full_span = if p.token.kind == token::Comma { span.to(p.token.span) } else { span };
+    p.sess.span_diagnostic.emit_err(errors::AsmOptAlreadyprovided { span, symbol, full_span });
 }
 
 /// Try to set the provided option in the provided `AsmArgs`.
@@ -497,8 +447,8 @@ fn expand_preparsed_asm(ecx: &mut ExtCtxt<'_>, args: AsmArgs) -> Option<ast::Inl
     // Register operands are implicitly used since they are not allowed to be
     // referenced in the template string.
     let mut used = vec![false; args.operands.len()];
-    for pos in &args.reg_args {
-        used[*pos] = true;
+    for pos in args.reg_args.iter() {
+        used[pos] = true;
     }
     let named_pos: FxHashMap<usize, Symbol> =
         args.named_args.iter().map(|(&sym, &idx)| (idx, sym)).collect();
@@ -600,11 +550,11 @@ fn expand_preparsed_asm(ecx: &mut ExtCtxt<'_>, args: AsmArgs) -> Option<ast::Inl
         if !parser.errors.is_empty() {
             let err = parser.errors.remove(0);
             let err_sp = template_span.from_inner(InnerSpan::new(err.span.start, err.span.end));
-            let msg = &format!("invalid asm template string: {}", err.description);
+            let msg = format!("invalid asm template string: {}", err.description);
             let mut e = ecx.struct_span_err(err_sp, msg);
             e.span_label(err_sp, err.label + " in asm template string");
             if let Some(note) = err.note {
-                e.note(&note);
+                e.note(note);
             }
             if let Some((label, span)) = err.secondary_label {
                 let err_sp = template_span.from_inner(InnerSpan::new(span.start, span.end));
@@ -632,10 +582,10 @@ fn expand_preparsed_asm(ecx: &mut ExtCtxt<'_>, args: AsmArgs) -> Option<ast::Inl
                         parse::ArgumentIs(idx) | parse::ArgumentImplicitlyIs(idx) => {
                             if idx >= args.operands.len()
                                 || named_pos.contains_key(&idx)
-                                || args.reg_args.contains(&idx)
+                                || args.reg_args.contains(idx)
                             {
                                 let msg = format!("invalid reference to argument at index {}", idx);
-                                let mut err = ecx.struct_span_err(span, &msg);
+                                let mut err = ecx.struct_span_err(span, msg);
                                 err.span_label(span, "from here");
 
                                 let positional_args = args.operands.len()
@@ -651,7 +601,7 @@ fn expand_preparsed_asm(ecx: &mut ExtCtxt<'_>, args: AsmArgs) -> Option<ast::Inl
                                     1 => format!("there is 1 {}argument", positional),
                                     x => format!("there are {} {}arguments", x, positional),
                                 };
-                                err.note(&msg);
+                                err.note(msg);
 
                                 if named_pos.contains_key(&idx) {
                                     err.span_label(args.operands[idx].1, "named argument");
@@ -659,7 +609,7 @@ fn expand_preparsed_asm(ecx: &mut ExtCtxt<'_>, args: AsmArgs) -> Option<ast::Inl
                                         args.operands[idx].1,
                                         "named arguments cannot be referenced by position",
                                     );
-                                } else if args.reg_args.contains(&idx) {
+                                } else if args.reg_args.contains(idx) {
                                     err.span_label(
                                         args.operands[idx].1,
                                         "explicit register argument",
@@ -688,7 +638,7 @@ fn expand_preparsed_asm(ecx: &mut ExtCtxt<'_>, args: AsmArgs) -> Option<ast::Inl
                                     ecx.struct_span_err(
                                         template_span
                                             .from_inner(InnerSpan::new(span.start, span.end)),
-                                        &msg,
+                                        msg,
                                     )
                                     .emit();
                                     None
@@ -705,11 +655,7 @@ fn expand_preparsed_asm(ecx: &mut ExtCtxt<'_>, args: AsmArgs) -> Option<ast::Inl
                             .ty_span
                             .map(|sp| template_sp.from_inner(InnerSpan::new(sp.start, sp.end)))
                             .unwrap_or(template_sp);
-                        ecx.struct_span_err(
-                            span,
-                            "asm template modifier must be a single character",
-                        )
-                        .emit();
+                        ecx.emit_err(errors::AsmModifierInvalid { span });
                         modifier = None;
                     }
 
@@ -758,7 +704,7 @@ fn expand_preparsed_asm(ecx: &mut ExtCtxt<'_>, args: AsmArgs) -> Option<ast::Inl
             let (sp, msg) = unused_operands.into_iter().next().unwrap();
             let mut err = ecx.struct_span_err(sp, msg);
             err.span_label(sp, msg);
-            err.help(&format!(
+            err.help(format!(
                 "if this argument is intentionally unused, \
                  consider using it in an asm comment: `\"/*{} */\"`",
                 help_str
@@ -773,7 +719,7 @@ fn expand_preparsed_asm(ecx: &mut ExtCtxt<'_>, args: AsmArgs) -> Option<ast::Inl
             for (sp, msg) in unused_operands {
                 err.span_label(sp, msg);
             }
-            err.help(&format!(
+            err.help(format!(
                 "if these arguments are intentionally unused, \
                  consider using them in an asm comment: `\"/*{} */\"`",
                 help_str
diff --git a/compiler/rustc_builtin_macros/src/assert.rs b/compiler/rustc_builtin_macros/src/assert.rs
index 0de424be2..ab4ea9c8c 100644
--- a/compiler/rustc_builtin_macros/src/assert.rs
+++ b/compiler/rustc_builtin_macros/src/assert.rs
@@ -61,7 +61,6 @@ pub fn expand_assert<'cx>(
                     delim: MacDelimiter::Parenthesis,
                     tokens,
                 }),
-                prior_type_ascription: None,
             })),
         );
         expr_if_not(cx, call_site_span, cond_expr, then, None)
diff --git a/compiler/rustc_builtin_macros/src/assert/context.rs b/compiler/rustc_builtin_macros/src/assert/context.rs
index c9e3cd486..b619e80e1 100644
--- a/compiler/rustc_builtin_macros/src/assert/context.rs
+++ b/compiler/rustc_builtin_macros/src/assert/context.rs
@@ -182,7 +182,6 @@ impl<'cx, 'a> Context<'cx, 'a> {
                     delim: MacDelimiter::Parenthesis,
                     tokens: initial.into_iter().chain(captures).collect::<TokenStream>(),
                 }),
-                prior_type_ascription: None,
             })),
         )
     }
@@ -234,10 +233,19 @@ impl<'cx, 'a> Context<'cx, 'a> {
             ExprKind::Cast(local_expr, _) => {
                 self.manage_cond_expr(local_expr);
             }
+            ExprKind::If(local_expr, _, _) => {
+                self.manage_cond_expr(local_expr);
+            }
             ExprKind::Index(prefix, suffix) => {
                 self.manage_cond_expr(prefix);
                 self.manage_cond_expr(suffix);
             }
+            ExprKind::Let(_, local_expr, _) => {
+                self.manage_cond_expr(local_expr);
+            }
+            ExprKind::Match(local_expr, _) => {
+                self.manage_cond_expr(local_expr);
+            }
             ExprKind::MethodCall(call) => {
                 for arg in &mut call.args {
                     self.manage_cond_expr(arg);
@@ -288,7 +296,7 @@ impl<'cx, 'a> Context<'cx, 'a> {
             ExprKind::Assign(_, _, _)
             | ExprKind::AssignOp(_, _, _)
             | ExprKind::Async(_, _)
-            | ExprKind::Await(_)
+            | ExprKind::Await(_, _)
             | ExprKind::Block(_, _)
             | ExprKind::Break(_, _)
             | ExprKind::Closure(_)
@@ -296,16 +304,14 @@ impl<'cx, 'a> Context<'cx, 'a> {
             | ExprKind::Continue(_)
             | ExprKind::Err
             | ExprKind::Field(_, _)
-            | ExprKind::FormatArgs(_)
             | ExprKind::ForLoop(_, _, _, _)
-            | ExprKind::If(_, _, _)
+            | ExprKind::FormatArgs(_)
             | ExprKind::IncludedBytes(..)
             | ExprKind::InlineAsm(_)
-            | ExprKind::Let(_, _, _)
             | ExprKind::Lit(_)
             | ExprKind::Loop(_, _, _)
             | ExprKind::MacCall(_)
-            | ExprKind::Match(_, _)
+            | ExprKind::OffsetOf(_, _)
             | ExprKind::Path(_, _)
             | ExprKind::Ret(_)
             | ExprKind::Try(_)
diff --git a/compiler/rustc_builtin_macros/src/cfg_eval.rs b/compiler/rustc_builtin_macros/src/cfg_eval.rs
index 750f1fe12..49401e9ca 100644
--- a/compiler/rustc_builtin_macros/src/cfg_eval.rs
+++ b/compiler/rustc_builtin_macros/src/cfg_eval.rs
@@ -119,7 +119,7 @@ impl<'ast> visit::Visitor<'ast> for CfgFinder {
         self.has_cfg_or_cfg_attr = self.has_cfg_or_cfg_attr
             || attr
                 .ident()
-                .map_or(false, |ident| ident.name == sym::cfg || ident.name == sym::cfg_attr);
+                .is_some_and(|ident| ident.name == sym::cfg || ident.name == sym::cfg_attr);
     }
 }
 
@@ -166,7 +166,9 @@ impl CfgEval<'_, '_> {
                     ))
                 },
                 Annotatable::Stmt(_) => |parser| {
-                    Ok(Annotatable::Stmt(P(parser.parse_stmt(ForceCollect::Yes)?.unwrap())))
+                    Ok(Annotatable::Stmt(P(parser
+                        .parse_stmt_without_recovery(false, ForceCollect::Yes)?
+                        .unwrap())))
                 },
                 Annotatable::Expr(_) => {
                     |parser| Ok(Annotatable::Expr(parser.parse_expr_force_collect()?))
diff --git a/compiler/rustc_builtin_macros/src/concat.rs b/compiler/rustc_builtin_macros/src/concat.rs
index b92964d03..50e88ae2e 100644
--- a/compiler/rustc_builtin_macros/src/concat.rs
+++ b/compiler/rustc_builtin_macros/src/concat.rs
@@ -32,6 +32,10 @@ pub fn expand_concat(
                 Ok(ast::LitKind::Bool(b)) => {
                     accumulator.push_str(&b.to_string());
                 }
+                Ok(ast::LitKind::CStr(..)) => {
+                    cx.span_err(e.span, "cannot concatenate a C string literal");
+                    has_errors = true;
+                }
                 Ok(ast::LitKind::Byte(..) | ast::LitKind::ByteStr(..)) => {
                     cx.emit_err(errors::ConcatBytestr { span: e.span });
                     has_errors = true;
diff --git a/compiler/rustc_builtin_macros/src/concat_bytes.rs b/compiler/rustc_builtin_macros/src/concat_bytes.rs
index ba639c0a9..5ef35af0a 100644
--- a/compiler/rustc_builtin_macros/src/concat_bytes.rs
+++ b/compiler/rustc_builtin_macros/src/concat_bytes.rs
@@ -18,6 +18,11 @@ fn invalid_type_err(
     };
     let snippet = cx.sess.source_map().span_to_snippet(span).ok();
     match ast::LitKind::from_token_lit(token_lit) {
+        Ok(ast::LitKind::CStr(_, _)) => {
+            // FIXME(c_str_literals): should concatenation of C string literals
+            // include the null bytes in the end?
+            cx.span_err(span, "cannot concatenate C string literals");
+        }
         Ok(ast::LitKind::Char(_)) => {
             let sugg =
                 snippet.map(|snippet| ConcatBytesInvalidSuggestion::CharLit { span, snippet });
diff --git a/compiler/rustc_builtin_macros/src/concat_idents.rs b/compiler/rustc_builtin_macros/src/concat_idents.rs
index 8c737f043..ee56d45c9 100644
--- a/compiler/rustc_builtin_macros/src/concat_idents.rs
+++ b/compiler/rustc_builtin_macros/src/concat_idents.rs
@@ -19,7 +19,7 @@ pub fn expand_concat_idents<'cx>(
     }
 
     let mut res_str = String::new();
-    for (i, e) in tts.into_trees().enumerate() {
+    for (i, e) in tts.trees().enumerate() {
         if i & 1 == 1 {
             match e {
                 TokenTree::Token(Token { kind: token::Comma, .. }, _) => {}
diff --git a/compiler/rustc_builtin_macros/src/deriving/bounds.rs b/compiler/rustc_builtin_macros/src/deriving/bounds.rs
index 0481a1189..2c8e6f99c 100644
--- a/compiler/rustc_builtin_macros/src/deriving/bounds.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/bounds.rs
@@ -27,3 +27,26 @@ pub fn expand_deriving_copy(
 
     trait_def.expand(cx, mitem, item, push);
 }
+
+pub fn expand_deriving_const_param_ty(
+    cx: &mut ExtCtxt<'_>,
+    span: Span,
+    mitem: &MetaItem,
+    item: &Annotatable,
+    push: &mut dyn FnMut(Annotatable),
+    is_const: bool,
+) {
+    let trait_def = TraitDef {
+        span,
+        path: path_std!(marker::ConstParamTy),
+        skip_path_as_bound: false,
+        needs_copy_as_bound_if_packed: false,
+        additional_bounds: Vec::new(),
+        supports_unions: false,
+        methods: Vec::new(),
+        associated_types: Vec::new(),
+        is_const,
+    };
+
+    trait_def.expand(cx, mitem, item, push);
+}
diff --git a/compiler/rustc_builtin_macros/src/deriving/clone.rs b/compiler/rustc_builtin_macros/src/deriving/clone.rs
index dfee2d3ce..988356374 100644
--- a/compiler/rustc_builtin_macros/src/deriving/clone.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/clone.rs
@@ -145,7 +145,7 @@ fn cs_clone_simple(
             }
             _ => cx.span_bug(
                 trait_span,
-                &format!("unexpected substructure in simple `derive({})`", name),
+                format!("unexpected substructure in simple `derive({})`", name),
             ),
         }
     }
@@ -179,10 +179,10 @@ fn cs_clone(
             vdata = &variant.data;
         }
         EnumTag(..) | AllFieldlessEnum(..) => {
-            cx.span_bug(trait_span, &format!("enum tags in `derive({})`", name,))
+            cx.span_bug(trait_span, format!("enum tags in `derive({})`", name,))
         }
         StaticEnum(..) | StaticStruct(..) => {
-            cx.span_bug(trait_span, &format!("associated function in `derive({})`", name))
+            cx.span_bug(trait_span, format!("associated function in `derive({})`", name))
         }
     }
 
@@ -194,7 +194,7 @@ fn cs_clone(
                     let Some(ident) = field.name else {
                         cx.span_bug(
                             trait_span,
-                            &format!("unnamed field in normal struct in `derive({})`", name,),
+                            format!("unnamed field in normal struct in `derive({})`", name,),
                         );
                     };
                     let call = subcall(cx, field);
diff --git a/compiler/rustc_builtin_macros/src/deriving/generic/mod.rs b/compiler/rustc_builtin_macros/src/deriving/generic/mod.rs
index e5a003315..4ba09335c 100644
--- a/compiler/rustc_builtin_macros/src/deriving/generic/mod.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/generic/mod.rs
@@ -1038,7 +1038,7 @@ impl<'a> MethodDef<'a> {
     /// `&self.x` because that might cause an unaligned ref. So for any trait
     /// method that takes a reference, we use a local block to force a copy.
     /// This requires that the field impl `Copy`.
-    /// ```
+    /// ```rust,ignore (example)
     /// # struct A { x: u8, y: u8 }
     /// impl PartialEq for A {
     ///     fn eq(&self, other: &A) -> bool {
@@ -1591,7 +1591,7 @@ impl<'a> TraitDef<'a> {
                                 BYTE_SLICE_IN_PACKED_STRUCT_WITH_DERIVE,
                                 sp,
                                 ast::CRATE_NODE_ID,
-                                &format!(
+                                format!(
                                     "{} slice in a packed struct that derives a built-in trait",
                                     ty
                                 ),
diff --git a/compiler/rustc_builtin_macros/src/edition_panic.rs b/compiler/rustc_builtin_macros/src/edition_panic.rs
index b2a21611d..ef0db23ff 100644
--- a/compiler/rustc_builtin_macros/src/edition_panic.rs
+++ b/compiler/rustc_builtin_macros/src/edition_panic.rs
@@ -63,7 +63,6 @@ fn expand<'cx>(
                     delim: MacDelimiter::Parenthesis,
                     tokens: tts,
                 }),
-                prior_type_ascription: None,
             })),
         ),
     )
diff --git a/compiler/rustc_builtin_macros/src/env.rs b/compiler/rustc_builtin_macros/src/env.rs
index 58c972738..8f64e3328 100644
--- a/compiler/rustc_builtin_macros/src/env.rs
+++ b/compiler/rustc_builtin_macros/src/env.rs
@@ -63,7 +63,8 @@ pub fn expand_env<'cx>(
         Some(exprs) => exprs.into_iter(),
     };
 
-    let Some((var, _style)) = expr_to_string(cx, exprs.next().unwrap(), "expected string literal") else {
+    let var_expr = exprs.next().unwrap();
+    let Some((var, _)) = expr_to_string(cx, var_expr.clone(), "expected string literal") else {
         return DummyResult::any(sp);
     };
 
@@ -71,7 +72,7 @@ pub fn expand_env<'cx>(
         None => None,
         Some(second) => match expr_to_string(cx, second, "expected string literal") {
             None => return DummyResult::any(sp),
-            Some((s, _style)) => Some(s),
+            Some((s, _)) => Some(s),
         },
     };
 
@@ -80,10 +81,15 @@ pub fn expand_env<'cx>(
     cx.sess.parse_sess.env_depinfo.borrow_mut().insert((var, value));
     let e = match value {
         None => {
+            // Use the string literal in the code in the diagnostic to avoid confusing diagnostics,
+            // e.g. when the literal contains escape sequences.
+            let ast::ExprKind::Lit(ast::token::Lit { kind: ast::token::LitKind::Str, symbol: original_var, ..}) = &var_expr.kind else {
+                unreachable!("`expr_to_string` ensures this is a string lit")
+            };
             cx.emit_err(errors::EnvNotDefined {
                 span: sp,
                 msg: custom_msg,
-                var,
+                var: *original_var,
                 help: custom_msg.is_none().then(|| help_for_missing_env_var(var.as_str())),
             });
             return DummyResult::any(sp);
diff --git a/compiler/rustc_builtin_macros/src/errors.rs b/compiler/rustc_builtin_macros/src/errors.rs
index 630f9b87b..d0d786460 100644
--- a/compiler/rustc_builtin_macros/src/errors.rs
+++ b/compiler/rustc_builtin_macros/src/errors.rs
@@ -1,5 +1,6 @@
 use rustc_errors::{
-    AddToDiagnostic, EmissionGuarantee, IntoDiagnostic, MultiSpan, SingleLabelManySpans,
+    AddToDiagnostic, DiagnosticBuilder, EmissionGuarantee, Handler, IntoDiagnostic, MultiSpan,
+    SingleLabelManySpans,
 };
 use rustc_macros::{Diagnostic, Subdiagnostic};
 use rustc_span::{symbol::Ident, Span, Symbol};
@@ -370,11 +371,12 @@ pub(crate) struct EnvNotDefined {
 // Hand-written implementation to support custom user messages
 impl<'a, G: EmissionGuarantee> IntoDiagnostic<'a, G> for EnvNotDefined {
     #[track_caller]
-    fn into_diagnostic(
-        self,
-        handler: &'a rustc_errors::Handler,
-    ) -> rustc_errors::DiagnosticBuilder<'a, G> {
+    fn into_diagnostic(self, handler: &'a Handler) -> DiagnosticBuilder<'a, G> {
         let mut diag = if let Some(msg) = self.msg {
+            #[expect(
+                rustc::untranslatable_diagnostic,
+                reason = "cannot translate user-provided messages"
+            )]
             handler.struct_diagnostic(msg.as_str())
         } else {
             handler.struct_diagnostic(crate::fluent_generated::builtin_macros_env_not_defined)
@@ -551,3 +553,182 @@ pub(crate) struct FormatPositionalMismatch {
     #[subdiagnostic]
     pub(crate) highlight: SingleLabelManySpans,
 }
+
+#[derive(Diagnostic)]
+#[diag(builtin_macros_test_case_non_item)]
+pub(crate) struct TestCaseNonItem {
+    #[primary_span]
+    pub(crate) span: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(builtin_macros_test_bad_fn)]
+pub(crate) struct TestBadFn {
+    #[primary_span]
+    pub(crate) span: Span,
+    #[label]
+    pub(crate) cause: Span,
+    pub(crate) kind: &'static str,
+}
+
+#[derive(Diagnostic)]
+#[diag(builtin_macros_asm_explicit_register_name)]
+pub(crate) struct AsmExplicitRegisterName {
+    #[primary_span]
+    pub(crate) span: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(builtin_macros_asm_mutually_exclusive)]
+pub(crate) struct AsmMutuallyExclusive {
+    #[primary_span]
+    pub(crate) spans: Vec<Span>,
+    pub(crate) opt1: &'static str,
+    pub(crate) opt2: &'static str,
+}
+
+#[derive(Diagnostic)]
+#[diag(builtin_macros_asm_pure_combine)]
+pub(crate) struct AsmPureCombine {
+    #[primary_span]
+    pub(crate) spans: Vec<Span>,
+}
+
+#[derive(Diagnostic)]
+#[diag(builtin_macros_asm_pure_no_output)]
+pub(crate) struct AsmPureNoOutput {
+    #[primary_span]
+    pub(crate) spans: Vec<Span>,
+}
+
+#[derive(Diagnostic)]
+#[diag(builtin_macros_asm_modifier_invalid)]
+pub(crate) struct AsmModifierInvalid {
+    #[primary_span]
+    pub(crate) span: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(builtin_macros_asm_requires_template)]
+pub(crate) struct AsmRequiresTemplate {
+    #[primary_span]
+    pub(crate) span: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(builtin_macros_asm_expected_comma)]
+pub(crate) struct AsmExpectedComma {
+    #[primary_span]
+    #[label]
+    pub(crate) span: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(builtin_macros_asm_underscore_input)]
+pub(crate) struct AsmUnderscoreInput {
+    #[primary_span]
+    pub(crate) span: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(builtin_macros_asm_sym_no_path)]
+pub(crate) struct AsmSymNoPath {
+    #[primary_span]
+    pub(crate) span: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(builtin_macros_asm_expected_other)]
+pub(crate) struct AsmExpectedOther {
+    #[primary_span]
+    #[label(builtin_macros_asm_expected_other)]
+    pub(crate) span: Span,
+    pub(crate) is_global_asm: bool,
+}
+
+#[derive(Diagnostic)]
+#[diag(builtin_macros_asm_duplicate_arg)]
+pub(crate) struct AsmDuplicateArg {
+    #[primary_span]
+    #[label(builtin_macros_arg)]
+    pub(crate) span: Span,
+    #[label]
+    pub(crate) prev: Span,
+    pub(crate) name: Symbol,
+}
+
+#[derive(Diagnostic)]
+#[diag(builtin_macros_asm_pos_after)]
+pub(crate) struct AsmPositionalAfter {
+    #[primary_span]
+    #[label(builtin_macros_pos)]
+    pub(crate) span: Span,
+    #[label(builtin_macros_named)]
+    pub(crate) named: Vec<Span>,
+    #[label(builtin_macros_explicit)]
+    pub(crate) explicit: Vec<Span>,
+}
+
+#[derive(Diagnostic)]
+#[diag(builtin_macros_asm_noreturn)]
+pub(crate) struct AsmNoReturn {
+    #[primary_span]
+    pub(crate) outputs_sp: Vec<Span>,
+}
+
+#[derive(Diagnostic)]
+#[diag(builtin_macros_global_asm_clobber_abi)]
+pub(crate) struct GlobalAsmClobberAbi {
+    #[primary_span]
+    pub(crate) spans: Vec<Span>,
+}
+
+pub(crate) struct AsmClobberNoReg {
+    pub(crate) spans: Vec<Span>,
+    pub(crate) clobbers: Vec<Span>,
+}
+
+impl<'a, G: EmissionGuarantee> IntoDiagnostic<'a, G> for AsmClobberNoReg {
+    fn into_diagnostic(self, handler: &'a Handler) -> DiagnosticBuilder<'a, G> {
+        let mut diag =
+            handler.struct_diagnostic(crate::fluent_generated::builtin_macros_asm_clobber_no_reg);
+        diag.set_span(self.spans.clone());
+        // eager translation as `span_labels` takes `AsRef<str>`
+        let lbl1 = handler.eagerly_translate_to_string(
+            crate::fluent_generated::builtin_macros_asm_clobber_abi,
+            [].into_iter(),
+        );
+        diag.span_labels(self.clobbers, &lbl1);
+        let lbl2 = handler.eagerly_translate_to_string(
+            crate::fluent_generated::builtin_macros_asm_clobber_outputs,
+            [].into_iter(),
+        );
+        diag.span_labels(self.spans, &lbl2);
+        diag
+    }
+}
+
+#[derive(Diagnostic)]
+#[diag(builtin_macros_asm_opt_already_provided)]
+pub(crate) struct AsmOptAlreadyprovided {
+    #[primary_span]
+    #[label]
+    pub(crate) span: Span,
+    pub(crate) symbol: Symbol,
+    #[suggestion(code = "", applicability = "machine-applicable", style = "tool-only")]
+    pub(crate) full_span: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(builtin_macros_test_runner_invalid)]
+pub(crate) struct TestRunnerInvalid {
+    #[primary_span]
+    pub(crate) span: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(builtin_macros_test_runner_nargs)]
+pub(crate) struct TestRunnerNargs {
+    #[primary_span]
+    pub(crate) span: Span,
+}
diff --git a/compiler/rustc_builtin_macros/src/format.rs b/compiler/rustc_builtin_macros/src/format.rs
index f0fc61d7c..c59a733c0 100644
--- a/compiler/rustc_builtin_macros/src/format.rs
+++ b/compiler/rustc_builtin_macros/src/format.rs
@@ -141,13 +141,7 @@ fn parse_args<'a>(ecx: &mut ExtCtxt<'a>, sp: Span, tts: TokenStream) -> PResult<
                         args: args
                             .named_args()
                             .iter()
-                            .filter_map(|a| {
-                                if let Some(ident) = a.kind.ident() {
-                                    Some((a, ident))
-                                } else {
-                                    None
-                                }
-                            })
+                            .filter_map(|a| a.kind.ident().map(|ident| (a, ident)))
                             .map(|(arg, n)| n.span.to(arg.expr.span))
                             .collect(),
                     });
@@ -622,14 +616,14 @@ fn report_missing_placeholders(
                         } else {
                             diag.span_note(
                                 sp,
-                                &format!("format specifiers use curly braces, and {}", trn),
+                                format!("format specifiers use curly braces, and {}", trn),
                             );
                         }
                     } else {
                         if success {
-                            diag.help(&format!("`{}` should be written as `{}`", sub, trn));
+                            diag.help(format!("`{}` should be written as `{}`", sub, trn));
                         } else {
-                            diag.note(&format!("`{}` should use curly braces, and {}", sub, trn));
+                            diag.note(format!("`{}` should use curly braces, and {}", sub, trn));
                         }
                     }
                 }
@@ -783,7 +777,7 @@ fn report_invalid_references(
                 has_precision_star = true;
                 e.span_label(
                     *span,
-                    &format!(
+                    format!(
                         "this precision flag adds an extra required argument at position {}, which is why there {} expected",
                         index,
                         if num_placeholders == 1 {
@@ -820,7 +814,7 @@ fn report_invalid_references(
         };
         e = ecx.struct_span_err(
             span,
-            &format!("invalid reference to positional {} ({})", arg_list, num_args_desc),
+            format!("invalid reference to positional {} ({})", arg_list, num_args_desc),
         );
         e.note("positional arguments are zero-based");
     }
diff --git a/compiler/rustc_builtin_macros/src/format_foreign.rs b/compiler/rustc_builtin_macros/src/format_foreign.rs
index bd9e903b6..bd5356575 100644
--- a/compiler/rustc_builtin_macros/src/format_foreign.rs
+++ b/compiler/rustc_builtin_macros/src/format_foreign.rs
@@ -562,15 +562,13 @@ pub(crate) mod printf {
         }
 
         if let Type = state {
-            drop(c);
             type_ = at.slice_between(next).unwrap();
 
             // Don't use `move_to!` here, as we *can* be at the end of the input.
             at = next;
         }
 
-        drop(c);
-        drop(next);
+        let _ = c; // to avoid never used value
 
         end = at;
         let position = InnerSpan::new(start.at, end.at);
diff --git a/compiler/rustc_builtin_macros/src/global_allocator.rs b/compiler/rustc_builtin_macros/src/global_allocator.rs
index 866cc5adb..f0d378d12 100644
--- a/compiler/rustc_builtin_macros/src/global_allocator.rs
+++ b/compiler/rustc_builtin_macros/src/global_allocator.rs
@@ -1,7 +1,7 @@
 use crate::util::check_builtin_macro_attribute;
 
 use rustc_ast::expand::allocator::{
-    AllocatorKind, AllocatorMethod, AllocatorTy, ALLOCATOR_METHODS,
+    global_fn_name, AllocatorMethod, AllocatorTy, ALLOCATOR_METHODS,
 };
 use rustc_ast::ptr::P;
 use rustc_ast::{self as ast, AttrVec, Expr, FnHeader, FnSig, Generics, Param, StmtKind};
@@ -40,8 +40,7 @@ pub fn expand(
 
     // Generate a bunch of new items using the AllocFnFactory
     let span = ecx.with_def_site_ctxt(item.span);
-    let f =
-        AllocFnFactory { span, ty_span, kind: AllocatorKind::Global, global: item.ident, cx: ecx };
+    let f = AllocFnFactory { span, ty_span, global: item.ident, cx: ecx };
 
     // Generate item statements for the allocator methods.
     let stmts = ALLOCATOR_METHODS.iter().map(|method| f.allocator_fn(method)).collect();
@@ -63,7 +62,6 @@ pub fn expand(
 struct AllocFnFactory<'a, 'b> {
     span: Span,
     ty_span: Span,
-    kind: AllocatorKind,
     global: Ident,
     cx: &'b ExtCtxt<'a>,
 }
@@ -92,7 +90,7 @@ impl AllocFnFactory<'_, '_> {
         }));
         let item = self.cx.item(
             self.span,
-            Ident::from_str_and_span(&self.kind.fn_name(method.name), self.span),
+            Ident::from_str_and_span(&global_fn_name(method.name), self.span),
             self.attrs(),
             kind,
         );
diff --git a/compiler/rustc_builtin_macros/src/lib.rs b/compiler/rustc_builtin_macros/src/lib.rs
index 37fbd03a6..ebf1448f5 100644
--- a/compiler/rustc_builtin_macros/src/lib.rs
+++ b/compiler/rustc_builtin_macros/src/lib.rs
@@ -1,7 +1,6 @@
 //! This crate contains implementations of built-in macros and other code generating facilities
 //! injecting code into the crate before it is lowered to HIR.
 
-#![allow(rustc::potential_query_instability)]
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
 #![feature(array_windows)]
 #![feature(box_patterns)]
@@ -24,7 +23,7 @@ use crate::deriving::*;
 use rustc_errors::{DiagnosticMessage, SubdiagnosticMessage};
 use rustc_expand::base::{MacroExpanderFn, ResolverExpand, SyntaxExtensionKind};
 use rustc_expand::proc_macro::BangProcMacro;
-use rustc_macros::fluent_messages;
+use rustc_fluent_macro::fluent_messages;
 use rustc_span::symbol::sym;
 
 mod alloc_error_handler;
@@ -116,6 +115,7 @@ pub fn register_builtin_macros(resolver: &mut dyn ResolverExpand) {
     register_derive! {
         Clone: clone::expand_deriving_clone,
         Copy: bounds::expand_deriving_copy,
+        ConstParamTy: bounds::expand_deriving_const_param_ty,
         Debug: debug::expand_deriving_debug,
         Default: default::expand_deriving_default,
         Eq: eq::expand_deriving_eq,
diff --git a/compiler/rustc_builtin_macros/src/proc_macro_harness.rs b/compiler/rustc_builtin_macros/src/proc_macro_harness.rs
index 378d5f39f..52b5601bb 100644
--- a/compiler/rustc_builtin_macros/src/proc_macro_harness.rs
+++ b/compiler/rustc_builtin_macros/src/proc_macro_harness.rs
@@ -194,7 +194,7 @@ impl<'a> Visitor<'a> for CollectProcMacros<'a> {
                     };
 
                     self.handler
-                        .struct_span_err(attr.span, &msg)
+                        .struct_span_err(attr.span, msg)
                         .span_label(prev_attr.span, "previous attribute here")
                         .emit();
 
@@ -219,7 +219,7 @@ impl<'a> Visitor<'a> for CollectProcMacros<'a> {
                 pprust::path_to_string(&attr.get_normal_item().path),
             );
 
-            self.handler.span_err(attr.span, &msg);
+            self.handler.span_err(attr.span, msg);
             return;
         }
 
@@ -233,7 +233,7 @@ impl<'a> Visitor<'a> for CollectProcMacros<'a> {
                 pprust::path_to_string(&attr.get_normal_item().path),
             );
 
-            self.handler.span_err(attr.span, &msg);
+            self.handler.span_err(attr.span, msg);
             return;
         }
 
diff --git a/compiler/rustc_builtin_macros/src/source_util.rs b/compiler/rustc_builtin_macros/src/source_util.rs
index 0b17e92ef..e613b904d 100644
--- a/compiler/rustc_builtin_macros/src/source_util.rs
+++ b/compiler/rustc_builtin_macros/src/source_util.rs
@@ -150,7 +150,7 @@ pub fn expand_include<'cx>(
                         if self.p.token != token::Eof {
                             let token = pprust::token_to_string(&self.p.token);
                             let msg = format!("expected item, found `{}`", token);
-                            self.p.struct_span_err(self.p.token.span, &msg).emit();
+                            self.p.struct_span_err(self.p.token.span, msg).emit();
                         }
 
                         break;
@@ -188,12 +188,12 @@ pub fn expand_include_str(
                 base::MacEager::expr(cx.expr_str(sp, interned_src))
             }
             Err(_) => {
-                cx.span_err(sp, &format!("{} wasn't a utf-8 file", file.display()));
+                cx.span_err(sp, format!("{} wasn't a utf-8 file", file.display()));
                 DummyResult::any(sp)
             }
         },
         Err(e) => {
-            cx.span_err(sp, &format!("couldn't read {}: {}", file.display(), e));
+            cx.span_err(sp, format!("couldn't read {}: {}", file.display(), e));
             DummyResult::any(sp)
         }
     }
@@ -221,7 +221,7 @@ pub fn expand_include_bytes(
             base::MacEager::expr(expr)
         }
         Err(e) => {
-            cx.span_err(sp, &format!("couldn't read {}: {}", file.display(), e));
+            cx.span_err(sp, format!("couldn't read {}: {}", file.display(), e));
             DummyResult::any(sp)
         }
     }
diff --git a/compiler/rustc_builtin_macros/src/test.rs b/compiler/rustc_builtin_macros/src/test.rs
index 79d8be248..49ee276af 100644
--- a/compiler/rustc_builtin_macros/src/test.rs
+++ b/compiler/rustc_builtin_macros/src/test.rs
@@ -1,3 +1,4 @@
+use crate::errors;
 /// The expansion from a test function to the appropriate test struct for libtest
 /// Ideally, this code would be in libtest but for efficiency and error messages it lives here.
 use crate::util::{check_builtin_macro_attribute, warn_on_duplicate_attribute};
@@ -40,12 +41,7 @@ pub fn expand_test_case(
             unreachable!()
         },
         _ => {
-            ecx.struct_span_err(
-                anno_item.span(),
-                "`#[test_case]` attribute is only allowed on items",
-            )
-            .emit();
-
+            ecx.emit_err(errors::TestCaseNonItem { span: anno_item.span() });
             return vec![];
         }
     };
@@ -533,15 +529,11 @@ fn has_test_signature(cx: &ExtCtxt<'_>, i: &ast::Item) -> bool {
     match &i.kind {
         ast::ItemKind::Fn(box ast::Fn { sig, generics, .. }) => {
             if let ast::Unsafe::Yes(span) = sig.header.unsafety {
-                sd.struct_span_err(i.span, "unsafe functions cannot be used for tests")
-                    .span_label(span, "`unsafe` because of this")
-                    .emit();
+                sd.emit_err(errors::TestBadFn { span: i.span, cause: span, kind: "unsafe" });
                 return false;
             }
             if let ast::Async::Yes { span, .. } = sig.header.asyncness {
-                sd.struct_span_err(i.span, "async functions cannot be used for tests")
-                    .span_label(span, "`async` because of this")
-                    .emit();
+                sd.emit_err(errors::TestBadFn { span: i.span, cause: span, kind: "async" });
                 return false;
             }
 
diff --git a/compiler/rustc_builtin_macros/src/test_harness.rs b/compiler/rustc_builtin_macros/src/test_harness.rs
index 80f497333..9bc1e27b4 100644
--- a/compiler/rustc_builtin_macros/src/test_harness.rs
+++ b/compiler/rustc_builtin_macros/src/test_harness.rs
@@ -19,6 +19,8 @@ use tracing::debug;
 
 use std::{iter, mem};
 
+use crate::errors;
+
 #[derive(Clone)]
 struct Test {
     span: Span,
@@ -230,7 +232,7 @@ fn generate_test_harness(
     let expn_id = ext_cx.resolver.expansion_for_ast_pass(
         DUMMY_SP,
         AstPass::TestHarness,
-        &[sym::test, sym::rustc_attrs],
+        &[sym::test, sym::rustc_attrs, sym::no_coverage],
         None,
     );
     let def_site = DUMMY_SP.with_def_site_ctxt(expn_id.to_expn_id());
@@ -311,6 +313,8 @@ fn mk_main(cx: &mut TestCtxt<'_>) -> P<ast::Item> {
 
     // #[rustc_main]
     let main_attr = ecx.attr_word(sym::rustc_main, sp);
+    // #[no_coverage]
+    let no_coverage_attr = ecx.attr_word(sym::no_coverage, sp);
 
     // pub fn main() { ... }
     let main_ret_ty = ecx.ty(sp, ast::TyKind::Tup(ThinVec::new()));
@@ -340,7 +344,7 @@ fn mk_main(cx: &mut TestCtxt<'_>) -> P<ast::Item> {
 
     let main = P(ast::Item {
         ident: main_id,
-        attrs: thin_vec![main_attr],
+        attrs: thin_vec![main_attr, no_coverage_attr],
         id: ast::DUMMY_NODE_ID,
         kind: main,
         vis: ast::Visibility { span: sp, kind: ast::VisibilityKind::Public, tokens: None },
@@ -385,11 +389,11 @@ fn get_test_runner(sd: &rustc_errors::Handler, krate: &ast::Crate) -> Option<ast
         [single] => match single.meta_item() {
             Some(meta_item) if meta_item.is_word() => return Some(meta_item.path.clone()),
             _ => {
-                sd.struct_span_err(span, "`test_runner` argument must be a path").emit();
+                sd.emit_err(errors::TestRunnerInvalid { span });
             }
         },
         _ => {
-            sd.struct_span_err(span, "`#![test_runner(..)]` accepts exactly 1 argument").emit();
+            sd.emit_err(errors::TestRunnerNargs { span });
         }
     }
     None
diff --git a/compiler/rustc_builtin_macros/src/trace_macros.rs b/compiler/rustc_builtin_macros/src/trace_macros.rs
index cc5ae6894..9c98723e1 100644
--- a/compiler/rustc_builtin_macros/src/trace_macros.rs
+++ b/compiler/rustc_builtin_macros/src/trace_macros.rs
@@ -8,7 +8,7 @@ pub fn expand_trace_macros(
     sp: Span,
     tt: TokenStream,
 ) -> Box<dyn base::MacResult + 'static> {
-    let mut cursor = tt.into_trees();
+    let mut cursor = tt.trees();
     let mut err = false;
     let value = match &cursor.next() {
         Some(TokenTree::Token(token, _)) if token.is_keyword(kw::True) => true,