Don't trigger unsafe_op_in_unsafe_fn for deprecated safe fns

Fixes #125875.
rust-lang · Jun 3, 2024 · e605228 · e605228
1 parent 621e957
commit e605228
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Showing 4 changed files with 109 additions and 34 deletions.
diff --git a/compiler/rustc_mir_build/src/check_unsafety.rs b/compiler/rustc_mir_build/src/check_unsafety.rs
@@ -88,6 +88,33 @@ impl<'tcx> UnsafetyVisitor<'_, 'tcx> {
         }
     }
 
+    fn emit_deprecated_safe_fn_call(&self, span: Span, kind: &UnsafeOpKind) -> bool {
+        match kind {
+            // Allow calls to deprecated-safe unsafe functions if the caller is
+            // from an edition before 2024.
+            &UnsafeOpKind::CallToUnsafeFunction(Some(id))
+                if !span.at_least_rust_2024()
+                    && self.tcx.has_attr(id, sym::rustc_deprecated_safe_2024) =>
+            {
+                self.tcx.emit_node_span_lint(
+                    DEPRECATED_SAFE,
+                    self.hir_context,
+                    span,
+                    CallToDeprecatedSafeFnRequiresUnsafe {
+                        span,
+                        function: with_no_trimmed_paths!(self.tcx.def_path_str(id)),
+                        sub: CallToDeprecatedSafeFnRequiresUnsafeSub {
+                            left: span.shrink_to_lo(),
+                            right: span.shrink_to_hi(),
+                        },
+                    },
+                );
+                true
+            }
+            _ => false,
+        }
+    }
+
     fn requires_unsafe(&mut self, span: Span, kind: UnsafeOpKind) {
         let unsafe_op_in_unsafe_fn_allowed = self.unsafe_op_in_unsafe_fn_allowed();
         match self.safety_context {
@@ -100,6 +127,7 @@ impl<'tcx> UnsafetyVisitor<'_, 'tcx> {
                 *used = true;
             }
             SafetyContext::UnsafeFn if unsafe_op_in_unsafe_fn_allowed => {}
+            SafetyContext::UnsafeFn if self.emit_deprecated_safe_fn_call(span, &kind) => {}
             SafetyContext::UnsafeFn => {
                 // unsafe_op_in_unsafe_fn is disallowed
                 kind.emit_unsafe_op_in_unsafe_fn_lint(
@@ -110,33 +138,14 @@ impl<'tcx> UnsafetyVisitor<'_, 'tcx> {
                 );
                 self.suggest_unsafe_block = false;
             }
-            SafetyContext::Safe => match kind {
-                // Allow calls to deprecated-safe unsafe functions if the
-                // caller is from an edition before 2024.
-                UnsafeOpKind::CallToUnsafeFunction(Some(id))
-                    if !span.at_least_rust_2024()
-                        && self.tcx.has_attr(id, sym::rustc_deprecated_safe_2024) =>
-                {
-                    self.tcx.emit_node_span_lint(
-                        DEPRECATED_SAFE,
-                        self.hir_context,
-                        span,
-                        CallToDeprecatedSafeFnRequiresUnsafe {
-                            span,
-                            function: with_no_trimmed_paths!(self.tcx.def_path_str(id)),
-                            sub: CallToDeprecatedSafeFnRequiresUnsafeSub {
-                                left: span.shrink_to_lo(),
-                                right: span.shrink_to_hi(),
-                            },
-                        },
-                    )
-                }
-                _ => kind.emit_requires_unsafe_err(
+            SafetyContext::Safe if self.emit_deprecated_safe_fn_call(span, &kind) => {},
+            SafetyContext::Safe => {
+                kind.emit_requires_unsafe_err(
                     self.tcx,
                     span,
                     self.hir_context,
                     unsafe_op_in_unsafe_fn_allowed,
-                ),
+                );
             },
         }
     }

diff --git a/tests/ui/rust-2024/unsafe-env.e2021.stderr b/tests/ui/rust-2024/unsafe-env.e2021.stderr
@@ -1,23 +1,42 @@
+error[E0133]: call to unsafe function `unsafe_fn` is unsafe and requires unsafe block
+  --> $DIR/unsafe-env.rs:15:9
+   |
+LL |         unsafe_fn();
+   |         ^^^^^^^^^^^ call to unsafe function
+   |
+   = note: for more information, see issue #71668 <https://github.com/rust-lang/rust/issues/71668>
+   = note: consult the function's documentation for information on how to avoid undefined behavior
+note: an unsafe function restricts its caller, but its body is safe by default
+  --> $DIR/unsafe-env.rs:9:1
+   |
+LL | unsafe fn unsafe_fn() {
+   | ^^^^^^^^^^^^^^^^^^^^^
+note: the lint level is defined here
+  --> $DIR/unsafe-env.rs:8:8
+   |
+LL | #[deny(unsafe_op_in_unsafe_fn)]
+   |        ^^^^^^^^^^^^^^^^^^^^^^
+
 error[E0133]: call to unsafe function `unsafe_fn` is unsafe and requires unsafe function or block
-  --> $DIR/unsafe-env.rs:23:5
+  --> $DIR/unsafe-env.rs:33:5
    |
 LL |     unsafe_fn();
    |     ^^^^^^^^^^^ call to unsafe function
    |
    = note: consult the function's documentation for information on how to avoid undefined behavior
 
 error: unnecessary `unsafe` block
-  --> $DIR/unsafe-env.rs:26:5
+  --> $DIR/unsafe-env.rs:36:5
    |
 LL |     unsafe {
    |     ^^^^^^ unnecessary `unsafe` block
    |
 note: the lint level is defined here
-  --> $DIR/unsafe-env.rs:11:8
+  --> $DIR/unsafe-env.rs:21:8
    |
 LL | #[deny(unused_unsafe)]
    |        ^^^^^^^^^^^^^
 
-error: aborting due to 2 previous errors
+error: aborting due to 3 previous errors
 
 For more information about this error, try `rustc --explain E0133`.
diff --git a/tests/ui/rust-2024/unsafe-env.e2024.stderr b/tests/ui/rust-2024/unsafe-env.e2024.stderr
@@ -1,39 +1,76 @@
+error[E0133]: call to unsafe function `std::env::set_var` is unsafe and requires unsafe block
+  --> $DIR/unsafe-env.rs:10:5
+   |
+LL |     env::set_var("FOO", "BAR");
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^ call to unsafe function
+   |
+   = note: for more information, see issue #71668 <https://github.com/rust-lang/rust/issues/71668>
+   = note: consult the function's documentation for information on how to avoid undefined behavior
+note: an unsafe function restricts its caller, but its body is safe by default
+  --> $DIR/unsafe-env.rs:9:1
+   |
+LL | unsafe fn unsafe_fn() {
+   | ^^^^^^^^^^^^^^^^^^^^^
+note: the lint level is defined here
+  --> $DIR/unsafe-env.rs:8:8
+   |
+LL | #[deny(unsafe_op_in_unsafe_fn)]
+   |        ^^^^^^^^^^^^^^^^^^^^^^
+
+error[E0133]: call to unsafe function `std::env::remove_var` is unsafe and requires unsafe block
+  --> $DIR/unsafe-env.rs:12:5
+   |
+LL |     env::remove_var("FOO");
+   |     ^^^^^^^^^^^^^^^^^^^^^^ call to unsafe function
+   |
+   = note: for more information, see issue #71668 <https://github.com/rust-lang/rust/issues/71668>
+   = note: consult the function's documentation for information on how to avoid undefined behavior
+
+error[E0133]: call to unsafe function `unsafe_fn` is unsafe and requires unsafe block
+  --> $DIR/unsafe-env.rs:15:9
+   |
+LL |         unsafe_fn();
+   |         ^^^^^^^^^^^ call to unsafe function
+   |
+   = note: for more information, see issue #71668 <https://github.com/rust-lang/rust/issues/71668>
+   = note: consult the function's documentation for information on how to avoid undefined behavior
+
 error[E0133]: call to unsafe function `set_var` is unsafe and requires unsafe block
-  --> $DIR/unsafe-env.rs:13:5
+  --> $DIR/unsafe-env.rs:23:5
    |
 LL |     env::set_var("FOO", "BAR");
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^ call to unsafe function
    |
    = note: consult the function's documentation for information on how to avoid undefined behavior
 
 error[E0133]: call to unsafe function `remove_var` is unsafe and requires unsafe block
-  --> $DIR/unsafe-env.rs:15:5
+  --> $DIR/unsafe-env.rs:25:5
    |
 LL |     env::remove_var("FOO");
    |     ^^^^^^^^^^^^^^^^^^^^^^ call to unsafe function
    |
    = note: consult the function's documentation for information on how to avoid undefined behavior
 
 error[E0133]: call to unsafe function `unsafe_fn` is unsafe and requires unsafe block
-  --> $DIR/unsafe-env.rs:23:5
+  --> $DIR/unsafe-env.rs:33:5
    |
 LL |     unsafe_fn();
    |     ^^^^^^^^^^^ call to unsafe function
    |
    = note: consult the function's documentation for information on how to avoid undefined behavior
 
 error: unnecessary `unsafe` block
-  --> $DIR/unsafe-env.rs:26:5
+  --> $DIR/unsafe-env.rs:36:5
    |
 LL |     unsafe {
    |     ^^^^^^ unnecessary `unsafe` block
    |
 note: the lint level is defined here
-  --> $DIR/unsafe-env.rs:11:8
+  --> $DIR/unsafe-env.rs:21:8
    |
 LL | #[deny(unused_unsafe)]
    |        ^^^^^^^^^^^^^
 
-error: aborting due to 4 previous errors
+error: aborting due to 7 previous errors
 
 For more information about this error, try `rustc --explain E0133`.
diff --git a/tests/ui/rust-2024/unsafe-env.rs b/tests/ui/rust-2024/unsafe-env.rs
@@ -5,7 +5,17 @@
 
 use std::env;
 
-unsafe fn unsafe_fn() {}
+#[deny(unsafe_op_in_unsafe_fn)]
+unsafe fn unsafe_fn() {
+    env::set_var("FOO", "BAR");
+    //[e2024]~^ ERROR call to unsafe function `std::env::set_var` is unsafe
+    env::remove_var("FOO");
+    //[e2024]~^ ERROR call to unsafe function `std::env::remove_var` is unsafe
+    if false {
+        unsafe_fn();
+        //~^ ERROR call to unsafe function `unsafe_fn` is unsafe
+    }
+}
 fn safe_fn() {}
 
 #[deny(unused_unsafe)]