Unrolled build for rust-lang#127106

Rollup merge of rust-lang#127106 - spastorino:improve-unsafe-extern-blocks-diagnostics, r=compiler-errors Improve unsafe extern blocks diagnostics Closes rust-lang#126327 For this code: ```rust extern { pub fn foo(); pub safe fn bar(); } ``` We get ... ``` error: items in unadorned `extern` blocks cannot have safety qualifiers --> test.rs:3:5 | 3 | pub safe fn bar(); | ^^^^^^^^^^^^^^^^^^ | help: add unsafe to this `extern` block | 1 | unsafe extern { | ++++++ error[E0658]: `unsafe extern {}` blocks and `safe` keyword are experimental --> test.rs:3:9 | 3 | pub safe fn bar(); | ^^^^ | = note: see issue rust-lang#123743 <rust-lang#123743> for more information = help: add `#![feature(unsafe_extern_blocks)]` to the crate attributes to enable error: aborting due to 2 previous errors For more information about this error, try `rustc --explain E0658`. ``` And then making the extern block unsafe, we get ... ``` error: extern block cannot be declared unsafe --> test.rs:1:1 | 1 | unsafe extern { | ^^^^^^ | = note: see issue rust-lang#123743 <rust-lang#123743> for more information = help: add `#![feature(unsafe_extern_blocks)]` to the crate attributes to enable error: items in unadorned `extern` blocks cannot have safety qualifiers --> test.rs:3:5 | 3 | pub safe fn bar(); | ^^^^^^^^^^^^^^^^^^ error[E0658]: `unsafe extern {}` blocks and `safe` keyword are experimental --> test.rs:3:9 | 3 | pub safe fn bar(); | ^^^^ | = note: see issue rust-lang#123743 <rust-lang#123743> for more information = help: add `#![feature(unsafe_extern_blocks)]` to the crate attributes to enable error: aborting due to 3 previous errors For more information about this error, try `rustc --explain E0658`. ``` r? ``@compiler-errors``

Author: rust-timer

compiler/rustc_ast_passes/src/ast_validation.rs

@@ -469,13 +469,18 @@ impl<'a> AstValidator<'a> {
  fn check_item_safety(&self, span: Span, safety: Safety) {
  match self.extern_mod_safety {
  Some(extern_safety) => {
- if matches!(safety, Safety::Unsafe(_) | Safety::Safe(_))
- && (extern_safety == Safety::Default || !self.features.unsafe_extern_blocks)
- {
- self.dcx().emit_err(errors::InvalidSafetyOnExtern {
- item_span: span,
- block: self.current_extern_span().shrink_to_lo(),
- });
+ if matches!(safety, Safety::Unsafe(_) | Safety::Safe(_)) {
+ if extern_safety == Safety::Default {
+ self.dcx().emit_err(errors::InvalidSafetyOnExtern {
+ item_span: span,
+ block: Some(self.current_extern_span().shrink_to_lo()),
+ });
+ } else if !self.features.unsafe_extern_blocks {
+ self.dcx().emit_err(errors::InvalidSafetyOnExtern {
+ item_span: span,
+ block: None,
+ });
+ }
  }
  }
  None => {
@@ -1098,7 +1103,15 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
  }
  }
  } else if let &Safety::Unsafe(span) = safety {
- this.dcx().emit_err(errors::UnsafeItem { span, kind: "extern block" });
+ let mut diag = this
+ .dcx()
+ .create_err(errors::UnsafeItem { span, kind: "extern block" });
+ rustc_session::parse::add_feature_diagnostics(
+ &mut diag,
+ self.session,
+ sym::unsafe_extern_blocks,
+ );
+ diag.emit();
  }
 
  if abi.is_none() {

compiler/rustc_ast_passes/src/errors.rs

@@ -222,7 +222,7 @@ pub struct InvalidSafetyOnExtern {
  #[primary_span]
  pub item_span: Span,
  #[suggestion(code = "unsafe ", applicability = "machine-applicable", style = "verbose")]
- pub block: Span,
+ pub block: Option<Span>,
 }
 
 #[derive(Diagnostic)]

tests/ui/feature-gates/feature-gate-unsafe-extern-blocks.stderr

@@ -3,6 +3,10 @@ error: extern block cannot be declared unsafe
  |
 LL | unsafe extern "C" {
  | ^^^^^^
+ |
+ = note: see issue #123743 <https://github.com/rust-lang/rust/issues/123743> for more information
+ = help: add `#![feature(unsafe_extern_blocks)]` to the crate attributes to enable
+ = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
 
 error[E0658]: `unsafe extern {}` blocks and `safe` keyword are experimental
  --> $DIR/feature-gate-unsafe-extern-blocks.rs:9:5

tests/ui/parser/unsafe-foreign-mod-2.stderr

@@ -9,17 +9,16 @@ error: extern block cannot be declared unsafe
  |
 LL | extern "C" unsafe {
  | ^^^^^^
+ |
+ = note: see issue #123743 <https://github.com/rust-lang/rust/issues/123743> for more information
+ = help: add `#![feature(unsafe_extern_blocks)]` to the crate attributes to enable
+ = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
 
 error: items in unadorned `extern` blocks cannot have safety qualifiers
  --> $DIR/unsafe-foreign-mod-2.rs:4:5
  |
 LL | unsafe fn foo();
  | ^^^^^^^^^^^^^^^^
- |
-help: add unsafe to this `extern` block
- |
-LL | unsafe extern "C" unsafe {
- | ++++++
 
 error: aborting due to 3 previous errors
 

tests/ui/parser/unsafe-foreign-mod.stderr

@@ -3,6 +3,10 @@ error: extern block cannot be declared unsafe
  |
 LL | unsafe extern "C" {
  | ^^^^^^
+ |
+ = note: see issue #123743 <https://github.com/rust-lang/rust/issues/123743> for more information
+ = help: add `#![feature(unsafe_extern_blocks)]` to the crate attributes to enable
+ = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
 
 error: aborting due to 1 previous error