Rollup merge of #85415 - LeSeulArtichaut:no-packed-borrow-unsafeck, r…

…=RalfJung Clean up remnants of BorrowOfPackedField cc #82525 which removed `BorrowOfPackedField` from unsafety-checking r? `@RalfJung`
rust-lang · May 18, 2021 · f4a0d97 · f4a0d97
2 parents 5f544bc + 62044b2
commit f4a0d97
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Showing 2 changed files with 22 additions and 43 deletions.
diff --git a/compiler/rustc_middle/src/mir/query.rs b/compiler/rustc_middle/src/mir/query.rs
@@ -32,7 +32,6 @@ pub enum UnsafetyViolationDetails {
  UseOfInlineAssembly,
  InitializingTypeWith,
  CastOfPointerToInt,
- BorrowOfPackedField,
  UseOfMutableStatic,
  UseOfExternStatic,
  DerefOfRawPointer,
@@ -64,11 +63,6 @@ impl UnsafetyViolationDetails {
  CastOfPointerToInt => {
  ("cast of pointer to int", "casting pointers to integers in constants")
  }
- BorrowOfPackedField => (
- "borrow of packed field",
- "fields of packed structs might be misaligned: dereferencing a misaligned pointer \
- or even just creating a misaligned reference is undefined behavior",
- ),
  UseOfMutableStatic => (
  "use of mutable static",
  "mutable statics can be mutated by multiple threads: aliasing violations or data \

diff --git a/compiler/rustc_mir_build/src/check_unsafety.rs b/compiler/rustc_mir_build/src/check_unsafety.rs
@@ -64,38 +64,30 @@ impl<'tcx> UnsafetyVisitor<'tcx> {
  SafetyContext::UnsafeFn if unsafe_op_in_unsafe_fn_allowed => {}
  SafetyContext::UnsafeFn => {
  // unsafe_op_in_unsafe_fn is disallowed
- if kind == BorrowOfPackedField {
- // FIXME handle borrows of packed fields
- } else {
- struct_span_err!(
- self.tcx.sess,
- span,
- E0133,
- "{} is unsafe and requires unsafe block",
- description,
- )
- .span_label(span, description)
- .note(note)
- .emit();
- }
+ struct_span_err!(
+ self.tcx.sess,
+ span,
+ E0133,
+ "{} is unsafe and requires unsafe block",
+ description,
+ )
+ .span_label(span, description)
+ .note(note)
+ .emit();
  }
  SafetyContext::Safe => {
- if kind == BorrowOfPackedField {
- // FIXME handle borrows of packed fields
- } else {
- let fn_sugg = if unsafe_op_in_unsafe_fn_allowed { " function or" } else { "" };
- struct_span_err!(
- self.tcx.sess,
- span,
- E0133,
- "{} is unsafe and requires unsafe{} block",
- description,
- fn_sugg,
- )
- .span_label(span, description)
- .note(note)
- .emit();
- }
+ let fn_sugg = if unsafe_op_in_unsafe_fn_allowed { " function or" } else { "" };
+ struct_span_err!(
+ self.tcx.sess,
+ span,
+ E0133,
+ "{} is unsafe and requires unsafe{} block",
+ description,
+ fn_sugg,
+ )
+ .span_label(span, description)
+ .note(note)
+ .emit();
  }
  }
  }
@@ -203,8 +195,6 @@ enum UnsafeOpKind {
  #[allow(dead_code)] // FIXME
  CastOfPointerToInt,
  #[allow(dead_code)] // FIXME
- BorrowOfPackedField,
- #[allow(dead_code)] // FIXME
  UseOfMutableStatic,
  #[allow(dead_code)] // FIXME
  UseOfExternStatic,
@@ -244,11 +234,6 @@ impl UnsafeOpKind {
  CastOfPointerToInt => {
  ("cast of pointer to int", "casting pointers to integers in constants")
  }
- BorrowOfPackedField => (
- "borrow of packed field",
- "fields of packed structs might be misaligned: dereferencing a misaligned pointer \
- or even just creating a misaligned reference is undefined behavior",
- ),
  UseOfMutableStatic => (
  "use of mutable static",
  "mutable statics can be mutated by multiple threads: aliasing violations or data \