Rollup of 7 pull requests

compiler/rustc_ast_lowering/src/expr.rs

@@ -915,14 +915,22 @@ impl<'hir> LoweringContext<'_, 'hir> {
             );
         }
         if !self.sess.features_untracked().destructuring_assignment {
-            feature_err(
+            let mut err = feature_err(
                 &self.sess.parse_sess,
                 sym::destructuring_assignment,
                 eq_sign_span,
                 "destructuring assignments are unstable",
-            )
-            .span_label(lhs.span, "cannot assign to this expression")
-            .emit();
+            );
+            err.span_label(lhs.span, "cannot assign to this expression");
+            if self.is_in_loop_condition {
+                err.span_suggestion_verbose(
+                    lhs.span.shrink_to_lo(),
+                    "you might have meant to use pattern destructuring",
+                    "let ".to_string(),
+                    rustc_errors::Applicability::MachineApplicable,
+                );
+            }
+            err.emit();
         }
 
         let mut assignments = vec![];

compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs

@@ -447,16 +447,20 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                                 // check if the RHS is from desugaring
                                 let opt_assignment_rhs_span =
                                     self.body.find_assignments(local).first().map(|&location| {
-                                        let stmt = &self.body[location.block].statements
-                                            [location.statement_index];
-                                        match stmt.kind {
-                                            mir::StatementKind::Assign(box (
-                                                _,
-                                                mir::Rvalue::Use(mir::Operand::Copy(place)),
-                                            )) => {
-                                                self.body.local_decls[place.local].source_info.span
-                                            }
-                                            _ => self.body.source_info(location).span,
+                                        if let Some(mir::Statement {
+                                            source_info: _,
+                                            kind:
+                                                mir::StatementKind::Assign(box (
+                                                    _,
+                                                    mir::Rvalue::Use(mir::Operand::Copy(place)),
+                                                )),
+                                        }) = self.body[location.block]
+                                            .statements
+                                            .get(location.statement_index)
+                                        {
+                                            self.body.local_decls[place.local].source_info.span
+                                        } else {
+                                            self.body.source_info(location).span
                                         }
                                     });
                                 match opt_assignment_rhs_span.and_then(|s| s.desugaring_kind()) {

compiler/rustc_codegen_cranelift/src/abi/pass_mode.rs

@@ -71,7 +71,7 @@ fn cast_target_to_abi_params(cast: CastTarget) -> SmallVec<[AbiParam; 2]> {
         .prefix
         .iter()
         .flatten()
-        .map(|&kind| reg_to_abi_param(Reg { kind, size: cast.prefix_chunk_size }))
+        .map(|&reg| reg_to_abi_param(reg))
         .chain((0..rest_count).map(|_| reg_to_abi_param(cast.rest.unit)))
         .collect::<SmallVec<_>>();
 

compiler/rustc_codegen_gcc/src/abi.rs

@@ -14,7 +14,7 @@ impl<'a, 'gcc, 'tcx> AbiBuilderMethods<'tcx> for Builder<'a, 'gcc, 'tcx> {
         // TODO(antoyo)
     }
 
-    fn get_param(&self, index: usize) -> Self::Value {
+    fn get_param(&mut self, index: usize) -> Self::Value {
         self.cx.current_func.borrow().expect("current func")
             .get_param(index as i32)
             .to_rvalue()
@@ -48,8 +48,8 @@ impl GccType for CastTarget {
         let mut args: Vec<_> = self
             .prefix
             .iter()
-            .flat_map(|option_kind| {
-                option_kind.map(|kind| Reg { kind, size: self.prefix_chunk_size }.gcc_type(cx))
+            .flat_map(|option_reg| {
+                option_reg.map(|reg| reg.gcc_type(cx))
             })
             .chain((0..rest_count).map(|_| rest_gcc_unit))
             .collect();

compiler/rustc_codegen_llvm/src/abi.rs

@@ -181,9 +181,7 @@ impl LlvmType for CastTarget {
         let mut args: Vec<_> = self
             .prefix
             .iter()
-            .flat_map(|option_kind| {
-                option_kind.map(|kind| Reg { kind, size: self.prefix_chunk_size }.llvm_type(cx))
-            })
+            .flat_map(|option_reg| option_reg.map(|reg| reg.llvm_type(cx)))
             .chain((0..rest_count).map(|_| rest_ll_unit))
             .collect();
 
@@ -466,6 +464,9 @@ impl<'tcx> FnAbiLlvmExt<'tcx> for FnAbi<'tcx, Ty<'tcx>> {
                     );
                 }
             }
+            PassMode::Cast(cast) => {
+                cast.attrs.apply_attrs_to_llfn(llvm::AttributePlace::ReturnValue, cx, llfn);
+            }
             _ => {}
         }
         for arg in &self.args {
@@ -497,8 +498,8 @@ impl<'tcx> FnAbiLlvmExt<'tcx> for FnAbi<'tcx, Ty<'tcx>> {
                     apply(a);
                     apply(b);
                 }
-                PassMode::Cast(_) => {
-                    apply(&ArgAttributes::new());
+                PassMode::Cast(cast) => {
+                    apply(&cast.attrs);
                 }
             }
         }
@@ -533,6 +534,13 @@ impl<'tcx> FnAbiLlvmExt<'tcx> for FnAbi<'tcx, Ty<'tcx>> {
                     );
                 }
             }
+            PassMode::Cast(cast) => {
+                cast.attrs.apply_attrs_to_callsite(
+                    llvm::AttributePlace::ReturnValue,
+                    &bx.cx,
+                    callsite,
+                );
+            }
             _ => {}
         }
         if let abi::Abi::Scalar(scalar) = self.ret.layout.abi {
@@ -577,8 +585,8 @@ impl<'tcx> FnAbiLlvmExt<'tcx> for FnAbi<'tcx, Ty<'tcx>> {
                     apply(bx.cx, a);
                     apply(bx.cx, b);
                 }
-                PassMode::Cast(_) => {
-                    apply(bx.cx, &ArgAttributes::new());
+                PassMode::Cast(cast) => {
+                    apply(bx.cx, &cast.attrs);
                 }
             }
         }
@@ -607,7 +615,7 @@ impl AbiBuilderMethods<'tcx> for Builder<'a, 'll, 'tcx> {
         fn_abi.apply_attrs_callsite(self, callsite)
     }
 
-    fn get_param(&self, index: usize) -> Self::Value {
+    fn get_param(&mut self, index: usize) -> Self::Value {
         llvm::get_param(self.llfn(), index as c_uint)
     }
 }

compiler/rustc_codegen_ssa/src/traits/abi.rs

@@ -4,5 +4,5 @@ use rustc_target::abi::call::FnAbi;
 
 pub trait AbiBuilderMethods<'tcx>: BackendTypes {
     fn apply_attrs_callsite(&mut self, fn_abi: &FnAbi<'tcx, Ty<'tcx>>, callsite: Self::Value);
-    fn get_param(&self, index: usize) -> Self::Value;
+    fn get_param(&mut self, index: usize) -> Self::Value;
 }

compiler/rustc_infer/src/traits/structural_impls.rs

@@ -70,6 +70,7 @@ impl<'tcx, O: TypeFoldable<'tcx>> TypeFoldable<'tcx> for traits::Obligation<'tcx
     }
 
     fn super_visit_with<V: TypeVisitor<'tcx>>(&self, visitor: &mut V) -> ControlFlow<V::BreakTy> {
-        self.predicate.visit_with(visitor)
+        self.predicate.visit_with(visitor)?;
+        self.param_env.visit_with(visitor)
     }
 }

compiler/rustc_target/src/abi/call/mips64.rs

@@ -1,4 +1,6 @@
-use crate::abi::call::{ArgAbi, ArgExtension, CastTarget, FnAbi, PassMode, Reg, RegKind, Uniform};
+use crate::abi::call::{
+    ArgAbi, ArgAttribute, ArgAttributes, ArgExtension, CastTarget, FnAbi, PassMode, Reg, Uniform,
+};
 use crate::abi::{self, HasDataLayout, Size, TyAbiInterface};
 
 fn extend_integer_width_mips<Ty>(arg: &mut ArgAbi<'_, Ty>, bits: u64) {
@@ -115,15 +117,15 @@ where
                             for _ in 0..((offset - last_offset).bits() / 64)
                                 .min((prefix.len() - prefix_index) as u64)
                             {
-                                prefix[prefix_index] = Some(RegKind::Integer);
+                                prefix[prefix_index] = Some(Reg::i64());
                                 prefix_index += 1;
                             }
 
                             if prefix_index == prefix.len() {
                                 break;
                             }
 
-                            prefix[prefix_index] = Some(RegKind::Float);
+                            prefix[prefix_index] = Some(Reg::f64());
                             prefix_index += 1;
                             last_offset = offset + Reg::f64().size;
                         }
@@ -137,8 +139,13 @@ where
     let rest_size = size - Size::from_bytes(8) * prefix_index as u64;
     arg.cast_to(CastTarget {
         prefix,
-        prefix_chunk_size: Size::from_bytes(8),
         rest: Uniform { unit: Reg::i64(), total: rest_size },
+        attrs: ArgAttributes {
+            regular: ArgAttribute::default(),
+            arg_ext: ArgExtension::None,
+            pointee_size: Size::ZERO,
+            pointee_align: None,
+        },
     });
 }
 

compiler/rustc_target/src/abi/call/mod.rs

@@ -214,9 +214,9 @@ impl Uniform {
 
 #[derive(Clone, Copy, PartialEq, Eq, Hash, Debug, HashStable_Generic)]
 pub struct CastTarget {
-    pub prefix: [Option<RegKind>; 8],
-    pub prefix_chunk_size: Size,
+    pub prefix: [Option<Reg>; 8],
     pub rest: Uniform,
+    pub attrs: ArgAttributes,
 }
 
 impl From<Reg> for CastTarget {
@@ -227,29 +227,48 @@ impl From<Reg> for CastTarget {
 
 impl From<Uniform> for CastTarget {
     fn from(uniform: Uniform) -> CastTarget {
-        CastTarget { prefix: [None; 8], prefix_chunk_size: Size::ZERO, rest: uniform }
+        CastTarget {
+            prefix: [None; 8],
+            rest: uniform,
+            attrs: ArgAttributes {
+                regular: ArgAttribute::default(),
+                arg_ext: ArgExtension::None,
+                pointee_size: Size::ZERO,
+                pointee_align: None,
+            },
+        }
     }
 }
 
 impl CastTarget {
     pub fn pair(a: Reg, b: Reg) -> CastTarget {
         CastTarget {
-            prefix: [Some(a.kind), None, None, None, None, None, None, None],
-            prefix_chunk_size: a.size,
+            prefix: [Some(a), None, None, None, None, None, None, None],
             rest: Uniform::from(b),
+            attrs: ArgAttributes {
+                regular: ArgAttribute::default(),
+                arg_ext: ArgExtension::None,
+                pointee_size: Size::ZERO,
+                pointee_align: None,
+            },
         }
     }
 
-    pub fn size<C: HasDataLayout>(&self, cx: &C) -> Size {
-        (self.prefix_chunk_size * self.prefix.iter().filter(|x| x.is_some()).count() as u64)
-            .align_to(self.rest.align(cx))
-            + self.rest.total
+    pub fn size<C: HasDataLayout>(&self, _cx: &C) -> Size {
+        let mut size = self.rest.total;
+        for i in 0..self.prefix.iter().count() {
+            match self.prefix[i] {
+                Some(v) => size += Size { raw: v.size.bytes() },
+                None => {}
+            }
+        }
+        return size;
     }
 
     pub fn align<C: HasDataLayout>(&self, cx: &C) -> Align {
         self.prefix
             .iter()
-            .filter_map(|x| x.map(|kind| Reg { kind, size: self.prefix_chunk_size }.align(cx)))
+            .filter_map(|x| x.map(|reg| reg.align(cx)))
             .fold(cx.data_layout().aggregate_align.abi.max(self.rest.align(cx)), |acc, align| {
                 acc.max(align)
             })