diff --git a/src/librustc_mir/borrow_check/move_errors.rs b/src/librustc_mir/borrow_check/move_errors.rs index 4aa38fb5f37..215ade5bd4d 100644 --- a/src/librustc_mir/borrow_check/move_errors.rs +++ b/src/librustc_mir/borrow_check/move_errors.rs @@ -87,6 +87,10 @@ impl<'a, 'gcx, 'tcx> MirBorrowckCtxt<'a, 'gcx, 'tcx> { cannot_move_out_of: IllegalMoveOrigin { location, kind }, } => { let stmt_source_info = self.mir.source_info(location); + // Note: that the only time we assign a place isn't a temporary + // to a user variable is when initializing it. + // If that ever stops being the case, then the ever initialized + // flow could be used. if let Some(StatementKind::Assign( Place::Local(local), Rvalue::Use(Operand::Move(move_from)), @@ -109,26 +113,16 @@ impl<'a, 'gcx, 'tcx> MirBorrowckCtxt<'a, 'gcx, 'tcx> { opt_ty_info: _, }))) = local_decl.is_user_variable { - // HACK use scopes to determine if this assignment is - // the initialization of a variable. - // FIXME(matthewjasper) This would probably be more - // reliable if it used the ever initialized dataflow - // but move errors are currently reported before the - // rest of borrowck has run. - if self - .mir - .is_sub_scope(local_decl.source_info.scope, stmt_source_info.scope) - { - self.append_binding_error( - grouped_errors, - kind, - move_from, - *local, - opt_match_place, - match_span, - ); - return; - } + self.append_binding_error( + grouped_errors, + kind, + move_from, + *local, + opt_match_place, + match_span, + stmt_source_info.span, + ); + return; } } grouped_errors.push(GroupedMoveError::OtherIllegalMove { @@ -147,6 +141,7 @@ impl<'a, 'gcx, 'tcx> MirBorrowckCtxt<'a, 'gcx, 'tcx> { bind_to: Local, match_place: &Option>, match_span: Span, + statement_span: Span, ) { debug!( "append_to_grouped_errors(match_place={:?}, match_span={:?})", @@ -173,13 +168,13 @@ impl<'a, 'gcx, 'tcx> MirBorrowckCtxt<'a, 'gcx, 'tcx> { debug!("found a new move error location"); // Don't need to point to x in let x = ... . - let binds_to = if from_simple_let { - vec![] + let (binds_to, span) = if from_simple_let { + (vec![], statement_span) } else { - vec![bind_to] + (vec![bind_to], match_span) }; grouped_errors.push(GroupedMoveError::MovesFromMatchPlace { - span: match_span, + span, move_from: match_place.clone(), kind, binds_to, diff --git a/src/test/ui/issue-20801.nll.stderr b/src/test/ui/issue-20801.nll.stderr index 0394309a6e2..fc94cc423c5 100644 --- a/src/test/ui/issue-20801.nll.stderr +++ b/src/test/ui/issue-20801.nll.stderr @@ -2,25 +2,37 @@ error[E0507]: cannot move out of borrowed content --> $DIR/issue-20801.rs:36:22 | LL | let a = unsafe { *mut_ref() }; - | ^^^^^^^^^^ cannot move out of borrowed content + | ^^^^^^^^^^ + | | + | cannot move out of borrowed content + | help: consider using a reference instead: `&*mut_ref()` error[E0507]: cannot move out of borrowed content --> $DIR/issue-20801.rs:39:22 | LL | let b = unsafe { *imm_ref() }; - | ^^^^^^^^^^ cannot move out of borrowed content + | ^^^^^^^^^^ + | | + | cannot move out of borrowed content + | help: consider using a reference instead: `&*imm_ref()` error[E0507]: cannot move out of borrowed content --> $DIR/issue-20801.rs:42:22 | LL | let c = unsafe { *mut_ptr() }; - | ^^^^^^^^^^ cannot move out of borrowed content + | ^^^^^^^^^^ + | | + | cannot move out of borrowed content + | help: consider using a reference instead: `&*mut_ptr()` error[E0507]: cannot move out of borrowed content --> $DIR/issue-20801.rs:45:22 | LL | let d = unsafe { *const_ptr() }; - | ^^^^^^^^^^^^ cannot move out of borrowed content + | ^^^^^^^^^^^^ + | | + | cannot move out of borrowed content + | help: consider using a reference instead: `&*const_ptr()` error: aborting due to 4 previous errors diff --git a/src/test/ui/nll/cannot-move-block-spans.nll.stderr b/src/test/ui/nll/cannot-move-block-spans.nll.stderr new file mode 100644 index 00000000000..814e11b6f06 --- /dev/null +++ b/src/test/ui/nll/cannot-move-block-spans.nll.stderr @@ -0,0 +1,85 @@ +error[E0507]: cannot move out of borrowed content + --> $DIR/cannot-move-block-spans.rs:15:15 + | +LL | let x = { *r }; //~ ERROR + | ^^ + | | + | cannot move out of borrowed content + | help: consider removing this dereference operator: `r` + +error[E0507]: cannot move out of borrowed content + --> $DIR/cannot-move-block-spans.rs:16:22 + | +LL | let y = unsafe { *r }; //~ ERROR + | ^^ + | | + | cannot move out of borrowed content + | help: consider removing this dereference operator: `r` + +error[E0507]: cannot move out of borrowed content + --> $DIR/cannot-move-block-spans.rs:17:26 + | +LL | let z = loop { break *r; }; //~ ERROR + | ^^ + | | + | cannot move out of borrowed content + | help: consider removing this dereference operator: `r` + +error[E0508]: cannot move out of type `[std::string::String; 2]`, a non-copy array + --> $DIR/cannot-move-block-spans.rs:21:15 + | +LL | let x = { arr[0] }; //~ ERROR + | ^^^^^^ + | | + | cannot move out of here + | help: consider using a reference instead: `&arr[0]` + +error[E0508]: cannot move out of type `[std::string::String; 2]`, a non-copy array + --> $DIR/cannot-move-block-spans.rs:22:22 + | +LL | let y = unsafe { arr[0] }; //~ ERROR + | ^^^^^^ + | | + | cannot move out of here + | help: consider using a reference instead: `&arr[0]` + +error[E0508]: cannot move out of type `[std::string::String; 2]`, a non-copy array + --> $DIR/cannot-move-block-spans.rs:23:26 + | +LL | let z = loop { break arr[0]; }; //~ ERROR + | ^^^^^^ + | | + | cannot move out of here + | help: consider using a reference instead: `&arr[0]` + +error[E0507]: cannot move out of borrowed content + --> $DIR/cannot-move-block-spans.rs:27:38 + | +LL | let x = { let mut u = 0; u += 1; *r }; //~ ERROR + | ^^ + | | + | cannot move out of borrowed content + | help: consider removing this dereference operator: `r` + +error[E0507]: cannot move out of borrowed content + --> $DIR/cannot-move-block-spans.rs:28:45 + | +LL | let y = unsafe { let mut u = 0; u += 1; *r }; //~ ERROR + | ^^ + | | + | cannot move out of borrowed content + | help: consider removing this dereference operator: `r` + +error[E0507]: cannot move out of borrowed content + --> $DIR/cannot-move-block-spans.rs:29:49 + | +LL | let z = loop { let mut u = 0; u += 1; break *r; u += 2; }; //~ ERROR + | ^^ + | | + | cannot move out of borrowed content + | help: consider removing this dereference operator: `r` + +error: aborting due to 9 previous errors + +Some errors occurred: E0507, E0508. +For more information about an error, try `rustc --explain E0507`. diff --git a/src/test/ui/nll/cannot-move-block-spans.rs b/src/test/ui/nll/cannot-move-block-spans.rs new file mode 100644 index 00000000000..5a84a4ca48e --- /dev/null +++ b/src/test/ui/nll/cannot-move-block-spans.rs @@ -0,0 +1,32 @@ +// Copyright 2018 The Rust Project Developers. See the COPYRIGHT +// file at the top-level directory of this distribution and at +// http://rust-lang.org/COPYRIGHT. +// +// Licensed under the Apache License, Version 2.0 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +// Test that the we point to the inner expression when moving out to initialize +// a variable, and that we don't give a useless suggestion such as &{ *r }. + +pub fn deref(r: &String) { + let x = { *r }; //~ ERROR + let y = unsafe { *r }; //~ ERROR + let z = loop { break *r; }; //~ ERROR +} + +pub fn index(arr: [String; 2]) { + let x = { arr[0] }; //~ ERROR + let y = unsafe { arr[0] }; //~ ERROR + let z = loop { break arr[0]; }; //~ ERROR +} + +pub fn additional_statement_cases(r: &String) { + let x = { let mut u = 0; u += 1; *r }; //~ ERROR + let y = unsafe { let mut u = 0; u += 1; *r }; //~ ERROR + let z = loop { let mut u = 0; u += 1; break *r; u += 2; }; //~ ERROR +} + +fn main() {} diff --git a/src/test/ui/nll/cannot-move-block-spans.stderr b/src/test/ui/nll/cannot-move-block-spans.stderr new file mode 100644 index 00000000000..d4956900239 --- /dev/null +++ b/src/test/ui/nll/cannot-move-block-spans.stderr @@ -0,0 +1,58 @@ +error[E0507]: cannot move out of borrowed content + --> $DIR/cannot-move-block-spans.rs:15:15 + | +LL | let x = { *r }; //~ ERROR + | ^^ cannot move out of borrowed content + +error[E0507]: cannot move out of borrowed content + --> $DIR/cannot-move-block-spans.rs:16:22 + | +LL | let y = unsafe { *r }; //~ ERROR + | ^^ cannot move out of borrowed content + +error[E0507]: cannot move out of borrowed content + --> $DIR/cannot-move-block-spans.rs:17:26 + | +LL | let z = loop { break *r; }; //~ ERROR + | ^^ cannot move out of borrowed content + +error[E0508]: cannot move out of type `[std::string::String; 2]`, a non-copy array + --> $DIR/cannot-move-block-spans.rs:21:15 + | +LL | let x = { arr[0] }; //~ ERROR + | ^^^^^^ cannot move out of here + +error[E0508]: cannot move out of type `[std::string::String; 2]`, a non-copy array + --> $DIR/cannot-move-block-spans.rs:22:22 + | +LL | let y = unsafe { arr[0] }; //~ ERROR + | ^^^^^^ cannot move out of here + +error[E0508]: cannot move out of type `[std::string::String; 2]`, a non-copy array + --> $DIR/cannot-move-block-spans.rs:23:26 + | +LL | let z = loop { break arr[0]; }; //~ ERROR + | ^^^^^^ cannot move out of here + +error[E0507]: cannot move out of borrowed content + --> $DIR/cannot-move-block-spans.rs:27:38 + | +LL | let x = { let mut u = 0; u += 1; *r }; //~ ERROR + | ^^ cannot move out of borrowed content + +error[E0507]: cannot move out of borrowed content + --> $DIR/cannot-move-block-spans.rs:28:45 + | +LL | let y = unsafe { let mut u = 0; u += 1; *r }; //~ ERROR + | ^^ cannot move out of borrowed content + +error[E0507]: cannot move out of borrowed content + --> $DIR/cannot-move-block-spans.rs:29:49 + | +LL | let z = loop { let mut u = 0; u += 1; break *r; u += 2; }; //~ ERROR + | ^^ cannot move out of borrowed content + +error: aborting due to 9 previous errors + +Some errors occurred: E0507, E0508. +For more information about an error, try `rustc --explain E0507`.