Rollup of 6 pull requests

.mailmap

@@ -31,6 +31,8 @@ Alexis Beingessner <a.beingessner@gmail.com>
 Alfie John <alfie@alfie.wtf> Alfie John <alfiej@fastmail.fm>
 Alona Enraght-Moony <code@alona.page> <nixon.emoony@gmail.com>
 Alona Enraght-Moony <code@alona.page> <nixon@caminus.local>
+Amanda Stjerna <mail@amandastjerna.se> <albin.stjerna@gmail.com>
+Amanda Stjerna <mail@amandastjerna.se> <amanda.stjerna@it.uu.se>
 Amos Onn <amosonn@gmail.com>
 Ana-Maria Mihalache <mihalacheana.maria@yahoo.com>
 Anatoly Ikorsky <aikorsky@gmail.com>

compiler/rustc_borrowck/src/diagnostics/mod.rs

@@ -470,7 +470,8 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             }
         }
 
-        ty.print(printer).unwrap().into_buffer()
+        ty.print(&mut printer).unwrap();
+        printer.into_buffer()
     }
 
     /// Returns the name of the provided `Ty` (that must be a reference)'s region with a
@@ -492,7 +493,8 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             bug!("ty for annotation of borrow region is not a reference");
         };
 
-        region.print(printer).unwrap().into_buffer()
+        region.print(&mut printer).unwrap();
+        printer.into_buffer()
     }
 }
 

compiler/rustc_const_eval/src/interpret/operand.rs

@@ -107,10 +107,10 @@ impl<Prov: Provenance> std::fmt::Display for ImmTy<'_, Prov> {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         /// Helper function for printing a scalar to a FmtPrinter
         fn p<'a, 'tcx, Prov: Provenance>(
-            cx: FmtPrinter<'a, 'tcx>,
+            cx: &mut FmtPrinter<'a, 'tcx>,
             s: Scalar<Prov>,
             ty: Ty<'tcx>,
-        ) -> Result<FmtPrinter<'a, 'tcx>, std::fmt::Error> {
+        ) -> Result<(), std::fmt::Error> {
             match s {
                 Scalar::Int(int) => cx.pretty_print_const_scalar_int(int, ty, true),
                 Scalar::Ptr(ptr, _sz) => {
@@ -125,8 +125,9 @@ impl<Prov: Provenance> std::fmt::Display for ImmTy<'_, Prov> {
             match self.imm {
                 Immediate::Scalar(s) => {
                     if let Some(ty) = tcx.lift(self.layout.ty) {
-                        let cx = FmtPrinter::new(tcx, Namespace::ValueNS);
-                        f.write_str(&p(cx, s, ty)?.into_buffer())?;
+                        let s =
+                            FmtPrinter::print_string(tcx, Namespace::ValueNS, |cx| p(cx, s, ty))?;
+                        f.write_str(&s)?;
                         return Ok(());
                     }
                     write!(f, "{:x}: {}", s, self.layout.ty)

compiler/rustc_const_eval/src/util/type_name.rs

@@ -18,11 +18,11 @@ impl<'tcx> Printer<'tcx> for AbsolutePathPrinter<'tcx> {
         self.tcx
     }
 
-    fn print_region(self, _region: ty::Region<'_>) -> Result<Self, PrintError> {
-        Ok(self)
+    fn print_region(&mut self, _region: ty::Region<'_>) -> Result<(), PrintError> {
+        Ok(())
     }
 
-    fn print_type(mut self, ty: Ty<'tcx>) -> Result<Self, PrintError> {
+    fn print_type(&mut self, ty: Ty<'tcx>) -> Result<(), PrintError> {
         match *ty.kind() {
             // Types without identity.
             ty::Bool
@@ -43,7 +43,7 @@ impl<'tcx> Printer<'tcx> for AbsolutePathPrinter<'tcx> {
             // Placeholders (all printed as `_` to uniformize them).
             ty::Param(_) | ty::Bound(..) | ty::Placeholder(_) | ty::Infer(_) | ty::Error(_) => {
                 write!(self, "_")?;
-                Ok(self)
+                Ok(())
             }
 
             // Types with identity (print the module path).
@@ -60,74 +60,74 @@ impl<'tcx> Printer<'tcx> for AbsolutePathPrinter<'tcx> {
         }
     }
 
-    fn print_const(self, ct: ty::Const<'tcx>) -> Result<Self, PrintError> {
+    fn print_const(&mut self, ct: ty::Const<'tcx>) -> Result<(), PrintError> {
         self.pretty_print_const(ct, false)
     }
 
     fn print_dyn_existential(
-        self,
+        &mut self,
         predicates: &'tcx ty::List<ty::PolyExistentialPredicate<'tcx>>,
-    ) -> Result<Self, PrintError> {
+    ) -> Result<(), PrintError> {
         self.pretty_print_dyn_existential(predicates)
     }
 
-    fn path_crate(mut self, cnum: CrateNum) -> Result<Self, PrintError> {
+    fn path_crate(&mut self, cnum: CrateNum) -> Result<(), PrintError> {
         self.path.push_str(self.tcx.crate_name(cnum).as_str());
-        Ok(self)
+        Ok(())
     }
 
     fn path_qualified(
-        self,
+        &mut self,
         self_ty: Ty<'tcx>,
         trait_ref: Option<ty::TraitRef<'tcx>>,
-    ) -> Result<Self, PrintError> {
+    ) -> Result<(), PrintError> {
         self.pretty_path_qualified(self_ty, trait_ref)
     }
 
     fn path_append_impl(
-        self,
-        print_prefix: impl FnOnce(Self) -> Result<Self, PrintError>,
+        &mut self,
+        print_prefix: impl FnOnce(&mut Self) -> Result<(), PrintError>,
         _disambiguated_data: &DisambiguatedDefPathData,
         self_ty: Ty<'tcx>,
         trait_ref: Option<ty::TraitRef<'tcx>>,
-    ) -> Result<Self, PrintError> {
+    ) -> Result<(), PrintError> {
         self.pretty_path_append_impl(
-            |mut cx| {
-                cx = print_prefix(cx)?;
+            |cx| {
+                print_prefix(cx)?;
 
                 cx.path.push_str("::");
 
-                Ok(cx)
+                Ok(())
             },
             self_ty,
             trait_ref,
         )
     }
 
     fn path_append(
-        mut self,
-        print_prefix: impl FnOnce(Self) -> Result<Self, PrintError>,
+        &mut self,
+        print_prefix: impl FnOnce(&mut Self) -> Result<(), PrintError>,
         disambiguated_data: &DisambiguatedDefPathData,
-    ) -> Result<Self, PrintError> {
-        self = print_prefix(self)?;
+    ) -> Result<(), PrintError> {
+        print_prefix(self)?;
 
         write!(self.path, "::{}", disambiguated_data.data).unwrap();
 
-        Ok(self)
+        Ok(())
     }
 
     fn path_generic_args(
-        mut self,
-        print_prefix: impl FnOnce(Self) -> Result<Self, PrintError>,
+        &mut self,
+        print_prefix: impl FnOnce(&mut Self) -> Result<(), PrintError>,
         args: &[GenericArg<'tcx>],
-    ) -> Result<Self, PrintError> {
-        self = print_prefix(self)?;
+    ) -> Result<(), PrintError> {
+        print_prefix(self)?;
         let args =
             args.iter().cloned().filter(|arg| !matches!(arg.unpack(), GenericArgKind::Lifetime(_)));
         if args.clone().next().is_some() {
             self.generic_delimiters(|cx| cx.comma_sep(args))
         } else {
-            Ok(self)
+            Ok(())
         }
     }
 }
@@ -136,31 +136,31 @@ impl<'tcx> PrettyPrinter<'tcx> for AbsolutePathPrinter<'tcx> {
     fn should_print_region(&self, _region: ty::Region<'_>) -> bool {
         false
     }
-    fn comma_sep<T>(mut self, mut elems: impl Iterator<Item = T>) -> Result<Self, PrintError>
+    fn comma_sep<T>(&mut self, mut elems: impl Iterator<Item = T>) -> Result<(), PrintError>
     where
         T: Print<'tcx, Self>,
     {
         if let Some(first) = elems.next() {
-            self = first.print(self)?;
+            first.print(self)?;
             for elem in elems {
                 self.path.push_str(", ");
-                self = elem.print(self)?;
+                elem.print(self)?;
             }
         }
-        Ok(self)
+        Ok(())
     }
 
     fn generic_delimiters(
-        mut self,
-        f: impl FnOnce(Self) -> Result<Self, PrintError>,
-    ) -> Result<Self, PrintError> {
+        &mut self,
+        f: impl FnOnce(&mut Self) -> Result<(), PrintError>,
+    ) -> Result<(), PrintError> {
         write!(self, "<")?;
 
-        self = f(self)?;
+        f(self)?;
 
         write!(self, ">")?;
 
-        Ok(self)
+        Ok(())
     }
 
     fn should_print_verbose(&self) -> bool {
@@ -177,5 +177,7 @@ impl Write for AbsolutePathPrinter<'_> {
 }
 
 pub fn type_name<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> String {
-    AbsolutePathPrinter { tcx, path: String::new() }.print_type(ty).unwrap().path
+    let mut printer = AbsolutePathPrinter { tcx, path: String::new() };
+    printer.print_type(ty).unwrap();
+    printer.path
 }

compiler/rustc_hir_typeck/src/pat.rs

@@ -12,6 +12,7 @@ use rustc_hir::pat_util::EnumerateAndAdjustIterator;
 use rustc_hir::{HirId, Pat, PatKind};
 use rustc_infer::infer;
 use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind};
+use rustc_middle::mir::interpret::ErrorHandled;
 use rustc_middle::ty::{self, Adt, BindingMode, Ty, TypeVisitableExt};
 use rustc_session::lint::builtin::NON_EXHAUSTIVE_OMITTED_PATTERNS;
 use rustc_span::edit_distance::find_best_match_for_name;
@@ -2164,7 +2165,19 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         len: ty::Const<'tcx>,
         min_len: u64,
     ) -> (Option<Ty<'tcx>>, Ty<'tcx>) {
-        let guar = if let Some(len) = len.try_eval_target_usize(self.tcx, self.param_env) {
+        let len = match len.eval(self.tcx, self.param_env, None) {
+            Ok(val) => val
+                .try_to_scalar()
+                .and_then(|scalar| scalar.try_to_int().ok())
+                .and_then(|int| int.try_to_target_usize(self.tcx).ok()),
+            Err(ErrorHandled::Reported(..)) => {
+                let guar = self.error_scrutinee_unfixed_length(span);
+                return (Some(Ty::new_error(self.tcx, guar)), arr_ty);
+            }
+            Err(ErrorHandled::TooGeneric(..)) => None,
+        };
+
+        let guar = if let Some(len) = len {
             // Now we know the length...
             if slice.is_none() {
                 // ...and since there is no variable-length pattern,

compiler/rustc_infer/src/infer/error_reporting/mod.rs

@@ -588,60 +588,60 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
                 self.tcx
             }
 
-            fn print_region(self, _region: ty::Region<'_>) -> Result<Self, PrintError> {
+            fn print_region(&mut self, _region: ty::Region<'_>) -> Result<(), PrintError> {
                 Err(fmt::Error)
             }
 
-            fn print_type(self, _ty: Ty<'tcx>) -> Result<Self, PrintError> {
+            fn print_type(&mut self, _ty: Ty<'tcx>) -> Result<(), PrintError> {
                 Err(fmt::Error)
             }
 
             fn print_dyn_existential(
-                self,
+                &mut self,
                 _predicates: &'tcx ty::List<ty::PolyExistentialPredicate<'tcx>>,
-            ) -> Result<Self, PrintError> {
+            ) -> Result<(), PrintError> {
                 Err(fmt::Error)
             }
 
-            fn print_const(self, _ct: ty::Const<'tcx>) -> Result<Self, PrintError> {
+            fn print_const(&mut self, _ct: ty::Const<'tcx>) -> Result<(), PrintError> {
                 Err(fmt::Error)
             }
 
-            fn path_crate(mut self, cnum: CrateNum) -> Result<Self, PrintError> {
+            fn path_crate(&mut self, cnum: CrateNum) -> Result<(), PrintError> {
                 self.segments = vec![self.tcx.crate_name(cnum).to_string()];
-                Ok(self)
+                Ok(())
             }
             fn path_qualified(
-                self,
+                &mut self,
                 _self_ty: Ty<'tcx>,
                 _trait_ref: Option<ty::TraitRef<'tcx>>,
-            ) -> Result<Self, PrintError> {
+            ) -> Result<(), PrintError> {
                 Err(fmt::Error)
             }
 
             fn path_append_impl(
-                self,
-                _print_prefix: impl FnOnce(Self) -> Result<Self, PrintError>,
+                &mut self,
+                _print_prefix: impl FnOnce(&mut Self) -> Result<(), PrintError>,
                 _disambiguated_data: &DisambiguatedDefPathData,
                 _self_ty: Ty<'tcx>,
                 _trait_ref: Option<ty::TraitRef<'tcx>>,
-            ) -> Result<Self, PrintError> {
+            ) -> Result<(), PrintError> {
                 Err(fmt::Error)
             }
             fn path_append(
-                mut self,
-                print_prefix: impl FnOnce(Self) -> Result<Self, PrintError>,
+                &mut self,
+                print_prefix: impl FnOnce(&mut Self) -> Result<(), PrintError>,
                 disambiguated_data: &DisambiguatedDefPathData,
-            ) -> Result<Self, PrintError> {
-                self = print_prefix(self)?;
+            ) -> Result<(), PrintError> {
+                print_prefix(self)?;
                 self.segments.push(disambiguated_data.to_string());
-                Ok(self)
+                Ok(())
             }
             fn path_generic_args(
-                self,
-                print_prefix: impl FnOnce(Self) -> Result<Self, PrintError>,
+                &mut self,
+                print_prefix: impl FnOnce(&mut Self) -> Result<(), PrintError>,
                 _args: &[GenericArg<'tcx>],
-            ) -> Result<Self, PrintError> {
+            ) -> Result<(), PrintError> {
                 print_prefix(self)
             }
         }
@@ -652,9 +652,8 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
             // let _ = [{struct Foo; Foo}, {struct Foo; Foo}];
             if did1.krate != did2.krate {
                 let abs_path = |def_id| {
-                    AbsolutePathPrinter { tcx: self.tcx, segments: vec![] }
-                        .print_def_path(def_id, &[])
-                        .map(|p| p.segments)
+                    let mut printer = AbsolutePathPrinter { tcx: self.tcx, segments: vec![] };
+                    printer.print_def_path(def_id, &[]).map(|_| printer.segments)
                 };
 
                 // We compare strings because DefPath can be different
@@ -1071,7 +1070,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
 
         let get_lifetimes = |sig| {
             use rustc_hir::def::Namespace;
-            let (_, sig, reg) = ty::print::FmtPrinter::new(self.tcx, Namespace::TypeNS)
+            let (sig, reg) = ty::print::FmtPrinter::new(self.tcx, Namespace::TypeNS)
                 .name_all_regions(sig)
                 .unwrap();
             let lts: Vec<String> = reg.into_values().map(|kind| kind.to_string()).collect();