diff --git a/compiler/rustc_hir_typeck/src/expr.rs b/compiler/rustc_hir_typeck/src/expr.rs index 3c5feb1ba51..5081285736e 100644 --- a/compiler/rustc_hir_typeck/src/expr.rs +++ b/compiler/rustc_hir_typeck/src/expr.rs @@ -2870,6 +2870,21 @@ fn check_expr_index( ); } } + + if base_t.is_unsafe_ptr() && idx_t.is_integral() { + err.multipart_suggestion( + "consider using `wrapping_add` or `add` for indexing into raw pointer", + vec![ + (base.span.between(idx.span), ".wrapping_add(".to_owned()), + ( + idx.span.shrink_to_hi().until(expr.span.shrink_to_hi()), + ")".to_owned(), + ), + ], + Applicability::MaybeIncorrect, + ); + } + let reported = err.emit(); self.tcx.ty_error(reported) } diff --git a/compiler/rustc_hir_typeck/src/op.rs b/compiler/rustc_hir_typeck/src/op.rs index b8bf2b69120..4f3d1d45679 100644 --- a/compiler/rustc_hir_typeck/src/op.rs +++ b/compiler/rustc_hir_typeck/src/op.rs @@ -521,6 +521,52 @@ fn check_overloaded_binop( } } } + + // Suggest using `add`, `offset` or `offset_from` for pointer - {integer}, + // pointer + {integer} or pointer - pointer. + if op.span.can_be_used_for_suggestions() { + match op.node { + hir::BinOpKind::Add if lhs_ty.is_unsafe_ptr() && rhs_ty.is_integral() => { + err.multipart_suggestion( + "consider using `wrapping_add` or `add` for pointer + {integer}", + vec![ + ( + lhs_expr.span.between(rhs_expr.span), + ".wrapping_add(".to_owned(), + ), + (rhs_expr.span.shrink_to_hi(), ")".to_owned()), + ], + Applicability::MaybeIncorrect, + ); + } + hir::BinOpKind::Sub => { + if lhs_ty.is_unsafe_ptr() && rhs_ty.is_integral() { + err.multipart_suggestion( + "consider using `wrapping_sub` or `sub` for pointer - {integer}", + vec![ + (lhs_expr.span.between(rhs_expr.span), ".wrapping_sub(".to_owned()), + (rhs_expr.span.shrink_to_hi(), ")".to_owned()), + ], + Applicability::MaybeIncorrect + ); + } + + if lhs_ty.is_unsafe_ptr() && rhs_ty.is_unsafe_ptr() { + err.multipart_suggestion( + "consider using `offset_from` for pointer - pointer if the pointers point to the same allocation", + vec![ + (lhs_expr.span.shrink_to_lo(), "unsafe { ".to_owned()), + (lhs_expr.span.between(rhs_expr.span), ".offset_from(".to_owned()), + (rhs_expr.span.shrink_to_hi(), ") }".to_owned()), + ], + Applicability::MaybeIncorrect + ); + } + } + _ => {} + } + } + let reported = err.emit(); self.tcx.ty_error(reported) } diff --git a/tests/ui/typeck/issue-112252-ptr-arithmetics-help.fixed b/tests/ui/typeck/issue-112252-ptr-arithmetics-help.fixed new file mode 100644 index 00000000000..bdb884f5431 --- /dev/null +++ b/tests/ui/typeck/issue-112252-ptr-arithmetics-help.fixed @@ -0,0 +1,10 @@ +// run-rustfix + +fn main() { + let _ptr1: *const u32 = std::ptr::null(); + let _ptr2: *const u32 = std::ptr::null(); + let _a = _ptr1.wrapping_add(5); //~ ERROR cannot add + let _b = _ptr1.wrapping_sub(5); //~ ERROR cannot subtract + let _c = unsafe { _ptr2.offset_from(_ptr1) }; //~ ERROR cannot subtract + let _d = _ptr1.wrapping_add(5); //~ ERROR cannot index +} diff --git a/tests/ui/typeck/issue-112252-ptr-arithmetics-help.rs b/tests/ui/typeck/issue-112252-ptr-arithmetics-help.rs new file mode 100644 index 00000000000..cf68850cc4d --- /dev/null +++ b/tests/ui/typeck/issue-112252-ptr-arithmetics-help.rs @@ -0,0 +1,10 @@ +// run-rustfix + +fn main() { + let _ptr1: *const u32 = std::ptr::null(); + let _ptr2: *const u32 = std::ptr::null(); + let _a = _ptr1 + 5; //~ ERROR cannot add + let _b = _ptr1 - 5; //~ ERROR cannot subtract + let _c = _ptr2 - _ptr1; //~ ERROR cannot subtract + let _d = _ptr1[5]; //~ ERROR cannot index +} diff --git a/tests/ui/typeck/issue-112252-ptr-arithmetics-help.stderr b/tests/ui/typeck/issue-112252-ptr-arithmetics-help.stderr new file mode 100644 index 00000000000..c55930da225 --- /dev/null +++ b/tests/ui/typeck/issue-112252-ptr-arithmetics-help.stderr @@ -0,0 +1,54 @@ +error[E0369]: cannot add `{integer}` to `*const u32` + --> $DIR/issue-112252-ptr-arithmetics-help.rs:6:20 + | +LL | let _a = _ptr1 + 5; + | ----- ^ - {integer} + | | + | *const u32 + | +help: consider using `wrapping_add` or `add` for pointer + {integer} + | +LL | let _a = _ptr1.wrapping_add(5); + | ~~~~~~~~~~~~~~ + + +error[E0369]: cannot subtract `{integer}` from `*const u32` + --> $DIR/issue-112252-ptr-arithmetics-help.rs:7:20 + | +LL | let _b = _ptr1 - 5; + | ----- ^ - {integer} + | | + | *const u32 + | +help: consider using `wrapping_sub` or `sub` for pointer - {integer} + | +LL | let _b = _ptr1.wrapping_sub(5); + | ~~~~~~~~~~~~~~ + + +error[E0369]: cannot subtract `*const u32` from `*const u32` + --> $DIR/issue-112252-ptr-arithmetics-help.rs:8:20 + | +LL | let _c = _ptr2 - _ptr1; + | ----- ^ ----- *const u32 + | | + | *const u32 + | +help: consider using `offset_from` for pointer - pointer if the pointers point to the same allocation + | +LL | let _c = unsafe { _ptr2.offset_from(_ptr1) }; + | ++++++++ ~~~~~~~~~~~~~ +++ + +error[E0608]: cannot index into a value of type `*const u32` + --> $DIR/issue-112252-ptr-arithmetics-help.rs:9:14 + | +LL | let _d = _ptr1[5]; + | ^^^^^^^^ + | +help: consider using `wrapping_add` or `add` for indexing into raw pointer + | +LL | let _d = _ptr1.wrapping_add(5); + | ~~~~~~~~~~~~~~ ~ + +error: aborting due to 4 previous errors + +Some errors have detailed explanations: E0369, E0608. +For more information about an error, try `rustc --explain E0369`.