Add checking for no_mangle to unsafe_code lint

compiler/rustc_lint/src/builtin.rs

@@ -236,6 +236,18 @@ impl UnsafeCode {
 
  cx.struct_span_lint(UNSAFE_CODE, span, decorate);
  }
+
+ fn report_overriden_symbol_name(&self, cx: &EarlyContext<'_>, span: Span, msg: &str) {
+ self.report_unsafe(cx, span, |lint| {
+ lint.build(msg)
+ .note(
+ "the linker's behavior with multiple libraries exporting duplicate symbol \
+ names is undefined and Rust cannot provide guarantees when you manually \
+ override them",
+ )
+ .emit();
+ })
+ }
 }
 
 impl EarlyLintPass for UnsafeCode {
@@ -277,6 +289,40 @@ impl EarlyLintPass for UnsafeCode {
  })
  }
 
+ ast::ItemKind::Fn(..) => {
+ if let Some(attr) = cx.sess().find_by_name(&it.attrs, sym::no_mangle) {
+ self.report_overriden_symbol_name(
+ cx,
+ attr.span,
+ "declaration of a `no_mangle` function",
+ );
+ }
+ if let Some(attr) = cx.sess().find_by_name(&it.attrs, sym::export_name) {
+ self.report_overriden_symbol_name(
+ cx,
+ attr.span,
+ "declaration of a function with `export_name`",
+ );
+ }
+ }
+
+ ast::ItemKind::Static(..) => {
+ if let Some(attr) = cx.sess().find_by_name(&it.attrs, sym::no_mangle) {
+ self.report_overriden_symbol_name(
+ cx,
+ attr.span,
+ "declaration of a `no_mangle` static",
+ );
+ }
+ if let Some(attr) = cx.sess().find_by_name(&it.attrs, sym::export_name) {
+ self.report_overriden_symbol_name(
+ cx,
+ attr.span,
+ "declaration of a static with `export_name`",
+ );
+ }
+ }
+
  _ => {}
  }
  }

src/test/ui/lint/lint-unsafe-code.rs

@@ -12,14 +12,28 @@ mod allowed_unsafe {
  unsafe fn also_allowed() {}
  unsafe trait AllowedUnsafe { }
  unsafe impl AllowedUnsafe for super::Bar {}
+ #[no_mangle] fn allowed2() {}
+ #[export_name = "foo"] fn allowed3() {}
 }
 
 macro_rules! unsafe_in_macro {
- () => {
+ () => {{
+ #[no_mangle] fn foo() {} //~ ERROR: declaration of a `no_mangle` function
+ #[no_mangle] static FOO: u32 = 5; //~ ERROR: declaration of a `no_mangle` static
+ #[export_name = "bar"] fn bar() {}
+ //~^ ERROR: declaration of a function with `export_name`
+ #[export_name = "BAR"] static BAR: u32 = 5;
+ //~^ ERROR: declaration of a static with `export_name`
  unsafe {} //~ ERROR: usage of an `unsafe` block
- }
+ }}
 }
 
+#[no_mangle] fn foo() {} //~ ERROR: declaration of a `no_mangle` function
+#[no_mangle] static FOO: u32 = 5; //~ ERROR: declaration of a `no_mangle` static
+
+#[export_name = "bar"] fn bar() {} //~ ERROR: declaration of a function with `export_name`
+#[export_name = "BAR"] static BAR: u32 = 5; //~ ERROR: declaration of a static with `export_name`
+
 unsafe fn baz() {} //~ ERROR: declaration of an `unsafe` function
 unsafe trait Foo {} //~ ERROR: declaration of an `unsafe` trait
 unsafe impl Foo for Bar {} //~ ERROR: implementation of an `unsafe` trait

src/test/ui/lint/lint-unsafe-code.stderr

@@ -1,89 +1,168 @@
-error: declaration of an `unsafe` function
- --> $DIR/lint-unsafe-code.rs:23:1
+error: declaration of a `no_mangle` function
+ --> $DIR/lint-unsafe-code.rs:31:1
  |
-LL | unsafe fn baz() {}
- | ^^^^^^^^^^^^^^^^^^
+LL | #[no_mangle] fn foo() {}
+ | ^^^^^^^^^^^^
  |
 note: the lint level is defined here
  --> $DIR/lint-unsafe-code.rs:3:9
  |
 LL | #![deny(unsafe_code)]
  | ^^^^^^^^^^^
+ = note: the linker's behavior with multiple libraries exporting duplicate symbol names is undefined and Rust cannot provide guarantees when you manually override them
+
+error: declaration of a `no_mangle` static
+ --> $DIR/lint-unsafe-code.rs:32:1
+ |
+LL | #[no_mangle] static FOO: u32 = 5;
+ | ^^^^^^^^^^^^
+ |
+ = note: the linker's behavior with multiple libraries exporting duplicate symbol names is undefined and Rust cannot provide guarantees when you manually override them
+
+error: declaration of a function with `export_name`
+ --> $DIR/lint-unsafe-code.rs:34:1
+ |
+LL | #[export_name = "bar"] fn bar() {}
+ | ^^^^^^^^^^^^^^^^^^^^^^
+ |
+ = note: the linker's behavior with multiple libraries exporting duplicate symbol names is undefined and Rust cannot provide guarantees when you manually override them
+
+error: declaration of a static with `export_name`
+ --> $DIR/lint-unsafe-code.rs:35:1
+ |
+LL | #[export_name = "BAR"] static BAR: u32 = 5;
+ | ^^^^^^^^^^^^^^^^^^^^^^
+ |
+ = note: the linker's behavior with multiple libraries exporting duplicate symbol names is undefined and Rust cannot provide guarantees when you manually override them
+
+error: declaration of an `unsafe` function
+ --> $DIR/lint-unsafe-code.rs:37:1
+ |
+LL | unsafe fn baz() {}
+ | ^^^^^^^^^^^^^^^^^^
 
 error: declaration of an `unsafe` trait
- --> $DIR/lint-unsafe-code.rs:24:1
+ --> $DIR/lint-unsafe-code.rs:38:1
  |
 LL | unsafe trait Foo {}
  | ^^^^^^^^^^^^^^^^^^^
 
 error: implementation of an `unsafe` trait
- --> $DIR/lint-unsafe-code.rs:25:1
+ --> $DIR/lint-unsafe-code.rs:39:1
  |
 LL | unsafe impl Foo for Bar {}
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: declaration of an `unsafe` method
- --> $DIR/lint-unsafe-code.rs:28:5
+ --> $DIR/lint-unsafe-code.rs:42:5
  |
 LL | unsafe fn baz(&self);
  | ^^^^^^^^^^^^^^^^^^^^^
 
 error: implementation of an `unsafe` method
- --> $DIR/lint-unsafe-code.rs:29:5
+ --> $DIR/lint-unsafe-code.rs:43:5
  |
 LL | unsafe fn provided(&self) {}
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: implementation of an `unsafe` method
- --> $DIR/lint-unsafe-code.rs:30:5
+ --> $DIR/lint-unsafe-code.rs:44:5
  |
 LL | unsafe fn provided_override(&self) {}
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: implementation of an `unsafe` method
- --> $DIR/lint-unsafe-code.rs:34:5
+ --> $DIR/lint-unsafe-code.rs:48:5
  |
 LL | unsafe fn baz(&self) {}
  | ^^^^^^^^^^^^^^^^^^^^^^^
 
 error: implementation of an `unsafe` method
- --> $DIR/lint-unsafe-code.rs:35:5
+ --> $DIR/lint-unsafe-code.rs:49:5
  |
 LL | unsafe fn provided_override(&self) {}
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: implementation of an `unsafe` method
- --> $DIR/lint-unsafe-code.rs:54:5
+ --> $DIR/lint-unsafe-code.rs:68:5
  |
 LL | unsafe fn provided_override(&self) {}
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: implementation of an `unsafe` method
- --> $DIR/lint-unsafe-code.rs:65:5
+ --> $DIR/lint-unsafe-code.rs:79:5
  |
 LL | unsafe fn provided(&self) {}
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: implementation of an `unsafe` method
- --> $DIR/lint-unsafe-code.rs:71:5
+ --> $DIR/lint-unsafe-code.rs:85:5
  |
 LL | unsafe fn provided(&self) {}
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: implementation of an `unsafe` method
- --> $DIR/lint-unsafe-code.rs:75:5
+ --> $DIR/lint-unsafe-code.rs:89:5
  |
 LL | unsafe fn baz(&self) {}
  | ^^^^^^^^^^^^^^^^^^^^^^^
 
 error: usage of an `unsafe` block
- --> $DIR/lint-unsafe-code.rs:86:5
+ --> $DIR/lint-unsafe-code.rs:100:5
  |
 LL | unsafe {}
  | ^^^^^^^^^
 
+error: declaration of a `no_mangle` function
+ --> $DIR/lint-unsafe-code.rs:21:9
+ |
+LL | #[no_mangle] fn foo() {}
+ | ^^^^^^^^^^^^
+...
+LL | unsafe_in_macro!()
+ | ------------------ in this macro invocation
+ |
+ = note: the linker's behavior with multiple libraries exporting duplicate symbol names is undefined and Rust cannot provide guarantees when you manually override them
+ = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error: declaration of a `no_mangle` static
+ --> $DIR/lint-unsafe-code.rs:22:9
+ |
+LL | #[no_mangle] static FOO: u32 = 5;
+ | ^^^^^^^^^^^^
+...
+LL | unsafe_in_macro!()
+ | ------------------ in this macro invocation
+ |
+ = note: the linker's behavior with multiple libraries exporting duplicate symbol names is undefined and Rust cannot provide guarantees when you manually override them
+ = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error: declaration of a function with `export_name`
+ --> $DIR/lint-unsafe-code.rs:23:9
+ |
+LL | #[export_name = "bar"] fn bar() {}
+ | ^^^^^^^^^^^^^^^^^^^^^^
+...
+LL | unsafe_in_macro!()
+ | ------------------ in this macro invocation
+ |
+ = note: the linker's behavior with multiple libraries exporting duplicate symbol names is undefined and Rust cannot provide guarantees when you manually override them
+ = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error: declaration of a static with `export_name`
+ --> $DIR/lint-unsafe-code.rs:25:9
+ |
+LL | #[export_name = "BAR"] static BAR: u32 = 5;
+ | ^^^^^^^^^^^^^^^^^^^^^^
+...
+LL | unsafe_in_macro!()
+ | ------------------ in this macro invocation
+ |
+ = note: the linker's behavior with multiple libraries exporting duplicate symbol names is undefined and Rust cannot provide guarantees when you manually override them
+ = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
+
 error: usage of an `unsafe` block
- --> $DIR/lint-unsafe-code.rs:19:9
+ --> $DIR/lint-unsafe-code.rs:27:9
  |
 LL | unsafe {}
  | ^^^^^^^^^
@@ -93,5 +172,5 @@ LL | unsafe_in_macro!()
  |
  = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: aborting due to 14 previous errors
+error: aborting due to 22 previous errors