Rollup merge of #106580 - Ezrashaw:remove-e0313, r=compiler-errors

remove unreachable error code `E0313`

Fixes #103742
Makes #103433 redundant

Implements removal of `E0313`. I agree with the linked issue that this error code is unreachable but if someone could confirm that would be great, are crater runs done for this sort of thing?

Also removed a redundant `// ignore-tidy-filelength` that I found while reading code.

cc ``@GuillaumeGomez`` #61137

5 files changed, 3 insertions, 46 deletions

diff --git a/compiler/rustc_error_codes/src/error_codes.rs b/compiler/rustc_error_codes/src/error_codes.rs
index 3fba2cf5749..76d5da19399 100644
--- a/compiler/rustc_error_codes/src/error_codes.rs
+++ b/compiler/rustc_error_codes/src/error_codes.rs
@@ -579,8 +579,7 @@ E0791: include_str!("./error_codes/E0791.md"),
 //  E0300, // unexpanded macro
 //  E0304, // expected signed integer constant
 //  E0305, // expected constant
-    E0313, // lifetime of borrowed pointer outlives lifetime of captured
-           // variable
+//  E0313, // removed: found unreachable
 //  E0314, // closure outlives stack frame
 //  E0315, // cannot invoke closure outside of its lifetime
 //  E0319, // trait impls for defaulted traits allowed just for structs/enums
diff --git a/compiler/rustc_infer/src/infer/error_reporting/mod.rs b/compiler/rustc_infer/src/infer/error_reporting/mod.rs
index 0644c7ada10..b02e7d73c51 100644
--- a/compiler/rustc_infer/src/infer/error_reporting/mod.rs
+++ b/compiler/rustc_infer/src/infer/error_reporting/mod.rs
@@ -1,4 +1,3 @@
-// ignore-tidy-filelength
 //! Error Reporting Code for the inference engine
 //!
 //! Because of the way inference, and in particular region inference,
diff --git a/compiler/rustc_infer/src/infer/error_reporting/note.rs b/compiler/rustc_infer/src/infer/error_reporting/note.rs
index d91ef882bc4..7bb79d7bda8 100644
--- a/compiler/rustc_infer/src/infer/error_reporting/note.rs
+++ b/compiler/rustc_infer/src/infer/error_reporting/note.rs
@@ -25,16 +25,6 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
             infer::Reborrow(span) => {
                 RegionOriginNote::Plain { span, msg: fluent::infer_reborrow }.add_to_diagnostic(err)
             }
-            infer::ReborrowUpvar(span, ref upvar_id) => {
-                let var_name = self.tcx.hir().name(upvar_id.var_path.hir_id);
-                RegionOriginNote::WithName {
-                    span,
-                    msg: fluent::infer_reborrow,
-                    name: &var_name.to_string(),
-                    continues: false,
-                }
-                .add_to_diagnostic(err);
-            }
             infer::RelateObjectBound(span) => {
                 RegionOriginNote::Plain { span, msg: fluent::infer_relate_object_bound }
                     .add_to_diagnostic(err);
@@ -162,33 +152,6 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
                 );
                 err
             }
-            infer::ReborrowUpvar(span, ref upvar_id) => {
-                let var_name = self.tcx.hir().name(upvar_id.var_path.hir_id);
-                let mut err = struct_span_err!(
-                    self.tcx.sess,
-                    span,
-                    E0313,
-                    "lifetime of borrowed pointer outlives lifetime of captured variable `{}`...",
-                    var_name
-                );
-                note_and_explain_region(
-                    self.tcx,
-                    &mut err,
-                    "...the borrowed pointer is valid for ",
-                    sub,
-                    "...",
-                    None,
-                );
-                note_and_explain_region(
-                    self.tcx,
-                    &mut err,
-                    &format!("...but `{}` is only valid for ", var_name),
-                    sup,
-                    "",
-                    None,
-                );
-                err
-            }
             infer::RelateObjectBound(span) => {
                 let mut err = struct_span_err!(
                     self.tcx.sess,
diff --git a/compiler/rustc_infer/src/infer/mod.rs b/compiler/rustc_infer/src/infer/mod.rs
index b17a465eb38..bc8bbd4be6a 100644
--- a/compiler/rustc_infer/src/infer/mod.rs
+++ b/compiler/rustc_infer/src/infer/mod.rs
@@ -409,9 +409,6 @@ pub enum SubregionOrigin<'tcx> {
     /// Creating a pointer `b` to contents of another reference
     Reborrow(Span),
 
-    /// Creating a pointer `b` to contents of an upvar
-    ReborrowUpvar(Span, ty::UpvarId),
-
     /// Data with type `Ty<'tcx>` was borrowed
     DataBorrowed(Ty<'tcx>, Span),
 
@@ -1954,7 +1951,6 @@ impl<'tcx> SubregionOrigin<'tcx> {
             RelateParamBound(a, ..) => a,
             RelateRegionParamBound(a) => a,
             Reborrow(a) => a,
-            ReborrowUpvar(a, _) => a,
             DataBorrowed(_, a) => a,
             ReferenceOutlivesReferent(_, a) => a,
             CompareImplItemObligation { span, .. } => span,
diff --git a/src/tools/tidy/src/error_codes.rs b/src/tools/tidy/src/error_codes.rs
index 4b0a62fac83..8d70335a9e7 100644
--- a/src/tools/tidy/src/error_codes.rs
+++ b/src/tools/tidy/src/error_codes.rs
@@ -31,8 +31,8 @@ const IGNORE_DOCTEST_CHECK: &[&str] = &["E0464", "E0570", "E0601", "E0602"];
 
 // Error codes that don't yet have a UI test. This list will eventually be removed.
 const IGNORE_UI_TEST_CHECK: &[&str] = &[
-    "E0313", "E0461", "E0465", "E0476", "E0490", "E0514", "E0523", "E0554", "E0640", "E0717",
-    "E0729", "E0789",
+    "E0461", "E0465", "E0476", "E0490", "E0514", "E0523", "E0554", "E0640", "E0717", "E0729",
+    "E0789",
 ];
 
 macro_rules! verbose_print {