Auto merge of #86399 - JohnTitor:rollup-qlm2dvz, r=JohnTitor

Rollup of 7 pull requests

Successful merges:

 - #85663 (Document Arc::from)
 - #85802 (Rename IoSlice(Mut)::advance to advance_slice and add IoSlice(Mut)::advance)
 - #85970 (Remove methods under Implementors on trait pages)
 - #86340 (Use better error message for hard errors in CTFE)
 - #86343 (Do not emit invalid suggestions on multiple mutable borrow errors)
 - #86355 (Remove invalid suggestions for assoc consts on placeholder type error)
 - #86389 (Make `sum()` and `product()` documentation hyperlinks refer to `Iterator` methods.)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

compiler/rustc_middle/src/mir/interpret/error.rs

@@ -518,4 +518,14 @@ impl InterpError<'_> {
             _ => false,
         }
     }
+
+    /// Should this error be reported as a hard error, preventing compilation, or a soft error,
+    /// causing a deny-by-default lint?
+    pub fn is_hard_err(&self) -> bool {
+        use InterpError::*;
+        match *self {
+            MachineStop(ref err) => err.is_hard_err(),
+            _ => false,
+        }
+    }
 }

compiler/rustc_mir/src/borrow_check/diagnostics/conflict_errors.rs

@@ -453,6 +453,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 &mut err,
                 "",
                 Some(borrow_span),
+                None,
             );
         err.buffer(&mut self.errors_buffer);
     }
@@ -498,6 +499,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 &mut err,
                 "",
                 None,
+                None,
             );
         err
     }
@@ -718,6 +720,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             &mut err,
             first_borrow_desc,
             None,
+            Some((issued_span, span)),
         );
 
         err
@@ -1076,6 +1079,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     &mut err,
                     "",
                     None,
+                    None,
                 );
             }
         } else {
@@ -1093,6 +1097,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 &mut err,
                 "",
                 None,
+                None,
             );
         }
 
@@ -1158,6 +1163,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             &mut err,
             "",
             None,
+            None,
         );
 
         err.buffer(&mut self.errors_buffer);
@@ -1236,6 +1242,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             &mut err,
             "",
             None,
+            None,
         );
 
         let within = if borrow_spans.for_generator() { " by generator" } else { "" };
@@ -1614,6 +1621,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             &mut err,
             "",
             None,
+            None,
         );
 
         self.explain_deref_coercion(loan, &mut err);