Don't reduce E0161 to a warning in NLL migrate mode

src/librustc_mir/borrow_check/nll/mod.rs

@@ -125,7 +125,6 @@ pub(in borrow_check) fn compute_regions<'cx, 'gcx, 'tcx>(
  flow_inits,
  move_data,
  elements,
- errors_buffer,
  );
 
  if let Some(all_facts) = &mut all_facts {

src/librustc_mir/borrow_check/nll/type_check/mod.rs

@@ -38,7 +38,6 @@ use rustc::traits::query::type_op;
 use rustc::traits::query::{Fallible, NoSolution};
 use rustc::ty::fold::TypeFoldable;
 use rustc::ty::{self, CanonicalTy, RegionVid, ToPolyTraitRef, Ty, TyCtxt, TyKind};
-use rustc_errors::Diagnostic;
 use std::fmt;
 use std::rc::Rc;
 use syntax_pos::{Span, DUMMY_SP};
@@ -106,8 +105,7 @@ mod relate_tys;
 /// - `liveness` -- results of a liveness computation on the MIR; used to create liveness
 /// constraints for the regions in the types of variables
 /// - `flow_inits` -- results of a maybe-init dataflow analysis
-/// - `move_data` -- move-data constructed when performing the maybe-init dataflow analysis
-/// - `errors_buffer` -- errors are sent here for future reporting
+/// - `move_data` -- move-data constructed when performing the maybe-init dataflow analysiss
 pub(crate) fn type_check<'gcx, 'tcx>(
  infcx: &InferCtxt<'_, 'gcx, 'tcx>,
  param_env: ty::ParamEnv<'gcx>,
@@ -120,7 +118,6 @@ pub(crate) fn type_check<'gcx, 'tcx>(
  flow_inits: &mut FlowAtLocation<MaybeInitializedPlaces<'_, 'gcx, 'tcx>>,
  move_data: &MoveData<'tcx>,
  elements: &Rc<RegionValueElements>,
- errors_buffer: &mut Vec<Diagnostic>,
 ) -> MirTypeckResults<'tcx> {
  let implicit_region_bound = infcx.tcx.mk_region(ty::ReVar(universal_regions.fr_fn_body));
  let mut constraints = MirTypeckRegionConstraints {
@@ -161,7 +158,6 @@ pub(crate) fn type_check<'gcx, 'tcx>(
  &region_bound_pairs,
  Some(implicit_region_bound),
  Some(&mut borrowck_context),
- Some(errors_buffer),
  |cx| {
  cx.equate_inputs_and_outputs(
  mir,
@@ -191,7 +187,6 @@ fn type_check_internal<'a, 'gcx, 'tcx, R>(
  region_bound_pairs: &'a [(ty::Region<'tcx>, GenericKind<'tcx>)],
  implicit_region_bound: Option<ty::Region<'tcx>>,
  borrowck_context: Option<&'a mut BorrowCheckContext<'a, 'tcx>>,
- errors_buffer: Option<&mut Vec<Diagnostic>>,
  mut extra: impl FnMut(&mut TypeChecker<'a, 'gcx, 'tcx>) -> R,
 ) -> R where {
  let mut checker = TypeChecker::new(
@@ -211,7 +206,7 @@ fn type_check_internal<'a, 'gcx, 'tcx, R>(
 
  if !errors_reported {
  // if verifier failed, don't do further checks to avoid ICEs
- checker.typeck_mir(mir, errors_buffer);
+ checker.typeck_mir(mir);
  }
 
  extra(&mut checker)
@@ -964,7 +959,6 @@ impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
  mir: &Mir<'tcx>,
  term: &Terminator<'tcx>,
  term_location: Location,
- errors_buffer: &mut Option<&mut Vec<Diagnostic>>,
  ) {
  debug!("check_terminator: {:?}", term);
  let tcx = self.tcx();
@@ -1044,7 +1038,7 @@ impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
  &sig,
  );
  let sig = self.normalize(sig, term_location);
- self.check_call_dest(mir, term, &sig, destination, term_location, errors_buffer);
+ self.check_call_dest(mir, term, &sig, destination, term_location);
 
  self.prove_predicates(
  sig.inputs().iter().map(|ty| ty::Predicate::WellFormed(ty)),
@@ -1118,7 +1112,6 @@ impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
  sig: &ty::FnSig<'tcx>,
  destination: &Option<(Place<'tcx>, BasicBlock)>,
  term_location: Location,
- errors_buffer: &mut Option<&mut Vec<Diagnostic>>,
  ) {
  let tcx = self.tcx();
  match *destination {
@@ -1152,7 +1145,7 @@ impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
  // this check is done at `check_local`.
  if self.tcx().features().unsized_locals {
  let span = term.source_info.span;
- self.ensure_place_sized(dest_ty, span, errors_buffer);
+ self.ensure_place_sized(dest_ty, span);
  }
  }
  None => {
@@ -1305,7 +1298,6 @@ impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
  mir: &Mir<'tcx>,
  local: Local,
  local_decl: &LocalDecl<'tcx>,
- errors_buffer: &mut Option<&mut Vec<Diagnostic>>,
  ) {
  match mir.local_kind(local) {
  LocalKind::ReturnPointer | LocalKind::Arg => {
@@ -1321,18 +1313,15 @@ impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
  }
 
  // When `#![feature(unsized_locals)]` is enabled, only function calls
- // are checked in `check_call_dest`.
+ // and nullary ops are checked in `check_call_dest`.
  if !self.tcx().features().unsized_locals {
  let span = local_decl.source_info.span;
  let ty = local_decl.ty;
- self.ensure_place_sized(ty, span, errors_buffer);
+ self.ensure_place_sized(ty, span);
  }
  }
 
- fn ensure_place_sized(&mut self,
- ty: Ty<'tcx>,
- span: Span,
- errors_buffer: &mut Option<&mut Vec<Diagnostic>>) {
+ fn ensure_place_sized(&mut self, ty: Ty<'tcx>, span: Span) {
  let tcx = self.tcx();
 
  // Erase the regions from `ty` to get a global type. The
@@ -1354,15 +1343,13 @@ impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
  cannot be statically determined",
  ty
  );
- if let Some(ref mut errors_buffer) = *errors_buffer {
- diag.buffer(errors_buffer);
- } else {
- // we're allowed to use emit() here because the
- // NLL migration will be turned on (and thus
- // errors will need to be buffered) *only if*
- // errors_buffer is Some.
- diag.emit();
- }
+
+ // While this is located in `nll::typeck` this error is not
+ // an NLL error, it's a required check to prevent creation
+ // of unsized rvalues in certain cases:
+ // * operand of a box expression
+ // * callee in a call expression
+ diag.emit();
  }
  }
  }
@@ -1437,6 +1424,12 @@ impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
  },
 
  Rvalue::NullaryOp(_, ty) => {
+ // Even with unsized locals cannot box an unsized value.
+ if self.tcx().features().unsized_locals {
+ let span = mir.source_info(location).span;
+ self.ensure_place_sized(ty, span);
+ }
+
  let trait_ref = ty::TraitRef {
  def_id: tcx.lang_items().sized_trait().unwrap(),
  substs: tcx.mk_substs_trait(ty, &[]),
@@ -1840,12 +1833,12 @@ impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
  })
  }
 
- fn typeck_mir(&mut self, mir: &Mir<'tcx>, mut errors_buffer: Option<&mut Vec<Diagnostic>>) {
+ fn typeck_mir(&mut self, mir: &Mir<'tcx>) {
  self.last_span = mir.span;
  debug!("run_on_mir: {:?}", mir.span);
 
  for (local, local_decl) in mir.local_decls.iter_enumerated() {
- self.check_local(mir, local, local_decl, &mut errors_buffer);
+ self.check_local(mir, local, local_decl);
  }
 
  for (block, block_data) in mir.basic_blocks().iter_enumerated() {
@@ -1861,7 +1854,7 @@ impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
  location.statement_index += 1;
  }
 
- self.check_terminator(mir, block_data.terminator(), location, &mut errors_buffer);
+ self.check_terminator(mir, block_data.terminator(), location);
  self.check_iscleanup(mir, block_data);
  }
  }
@@ -1918,7 +1911,6 @@ impl MirPass for TypeckMir {
  &[],
  None,
  None,
- None,
  |_| (),
  );
 

src/test/ui/dst/dst-index.nll.stderr

@@ -4,18 +4,18 @@ error[E0161]: cannot move a value of type str: the size of str cannot be statica
 LL | S[0];
  | ^^^^
 
-error[E0507]: cannot move out of borrowed content
- --> $DIR/dst-index.rs:41:5
- |
-LL | S[0];
- | ^^^^ cannot move out of borrowed content
-
 error[E0161]: cannot move a value of type dyn std::fmt::Debug: the size of dyn std::fmt::Debug cannot be statically determined
  --> $DIR/dst-index.rs:44:5
  |
 LL | T[0];
  | ^^^^
 
+error[E0507]: cannot move out of borrowed content
+ --> $DIR/dst-index.rs:41:5
+ |
+LL | S[0];
+ | ^^^^ cannot move out of borrowed content
+
 error[E0507]: cannot move out of borrowed content
  --> $DIR/dst-index.rs:44:5
  |

src/test/ui/dst/dst-rvalue.nll.stderr

@@ -4,18 +4,18 @@ error[E0161]: cannot move a value of type str: the size of str cannot be statica
 LL | let _x: Box<str> = box *"hello world";
  | ^^^^^^^^^^^^^^
 
-error[E0507]: cannot move out of borrowed content
- --> $DIR/dst-rvalue.rs:16:28
- |
-LL | let _x: Box<str> = box *"hello world";
- | ^^^^^^^^^^^^^^ cannot move out of borrowed content
-
 error[E0161]: cannot move a value of type [isize]: the size of [isize] cannot be statically determined
  --> $DIR/dst-rvalue.rs:21:32
  |
 LL | let _x: Box<[isize]> = box *array;
  | ^^^^^^
 
+error[E0507]: cannot move out of borrowed content
+ --> $DIR/dst-rvalue.rs:16:28
+ |
+LL | let _x: Box<str> = box *"hello world";
+ | ^^^^^^^^^^^^^^ cannot move out of borrowed content
+
 error[E0508]: cannot move out of type `[isize]`, a non-copy slice
  --> $DIR/dst-rvalue.rs:21:32
  |

src/test/ui/error-codes/E0161.ast.stderr

@@ -0,0 +1,9 @@
+error[E0161]: cannot move a value of type [i32]: the size of [i32] cannot be statically determined
+ --> $DIR/E0161.rs:32:9
+ |
+LL | box *x; //~ ERROR E0161
+ | ^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0161`.

src/test/ui/error-codes/E0161.astul.stderr

@@ -0,0 +1,9 @@
+error[E0161]: cannot move a value of type [i32]: the size of [i32] cannot be statically determined
+ --> $DIR/E0161.rs:32:5
+ |
+LL | box *x; //~ ERROR E0161
+ | ^^^^^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0161`.

src/test/ui/error-codes/E0161.edition.stderr

@@ -0,0 +1,9 @@
+error[E0161]: cannot move a value of type [i32]: the size of [i32] cannot be statically determined
+ --> $DIR/E0161.rs:32:9
+ |
+LL | box *x; //~ ERROR E0161
+ | ^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0161`.

src/test/ui/error-codes/E0161.editionul.stderr

@@ -0,0 +1,9 @@
+error[E0161]: cannot move a value of type [i32]: the size of [i32] cannot be statically determined
+ --> $DIR/E0161.rs:32:5
+ |
+LL | box *x; //~ ERROR E0161
+ | ^^^^^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0161`.

src/test/ui/error-codes/E0161.nll.stderr

@@ -0,0 +1,9 @@
+error[E0161]: cannot move a value of type [i32]: the size of [i32] cannot be statically determined
+ --> $DIR/E0161.rs:32:9
+ |
+LL | box *x; //~ ERROR E0161
+ | ^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0161`.

src/test/ui/error-codes/E0161.nllul.stderr

@@ -0,0 +1,9 @@
+error[E0161]: cannot move a value of type [i32]: the size of [i32] cannot be statically determined
+ --> $DIR/E0161.rs:32:5
+ |
+LL | box *x; //~ ERROR E0161
+ | ^^^^^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0161`.

src/test/ui/error-codes/E0161.rs

@@ -8,9 +8,28 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+// ignore-compare-mode-nll
+
+// Check that E0161 is a hard error in all possible configurations that might
+// affect it.
+
+// revisions: ast nll zflags edition astul nllul zflagsul editionul
+//[zflags]compile-flags: -Z borrowck=migrate -Z two-phase-borrows
+//[edition]edition:2018
+//[zflagsul]compile-flags: -Z borrowck=migrate -Z two-phase-borrows
+//[editionul]edition:2018
+
+#![cfg_attr(nll, feature(nll))]
+#![cfg_attr(nllul, feature(nll))]
+#![cfg_attr(astul, feature(unsized_locals))]
+#![cfg_attr(zflagsul, feature(unsized_locals))]
+#![cfg_attr(nllul, feature(unsized_locals))]
+#![cfg_attr(editionul, feature(unsized_locals))]
+
 #![feature(box_syntax)]
 
-fn main() {
- let _x: Box<str> = box *"hello"; //~ ERROR E0161
- //~^ ERROR E0507
+fn foo(x: Box<[i32]>) {
+ box *x; //~ ERROR E0161
 }
+
+fn main() {}

src/test/ui/error-codes/E0161.zflags.stderr

@@ -0,0 +1,9 @@
+error[E0161]: cannot move a value of type [i32]: the size of [i32] cannot be statically determined
+ --> $DIR/E0161.rs:32:9
+ |
+LL | box *x; //~ ERROR E0161
+ | ^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0161`.

src/test/ui/error-codes/E0161.zflagsul.stderr

@@ -0,0 +1,9 @@
+error[E0161]: cannot move a value of type [i32]: the size of [i32] cannot be statically determined
+ --> $DIR/E0161.rs:32:5
+ |
+LL | box *x; //~ ERROR E0161
+ | ^^^^^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0161`.