Auto merge of #100740 - Dylan-DPC:rollup-0td6yq4, r=Dylan-DPC

Rollup of 9 pull requests

Successful merges:

 - #99576 (Do not allow `Drop` impl on foreign fundamental types)
 - #100081 (never consider unsafe blocks unused if they would be required with deny(unsafe_op_in_unsafe_fn))
 - #100208 (make NOP dyn casts not require anything about the vtable)
 - #100494 (Cleanup rustdoc themes)
 - #100522 (Only check the `DefId` for the recursion check in MIR inliner.)
 - #100592 (Manually implement Debug for ImportKind.)
 - #100598 (Don't fix builtin index when Where clause is found)
 - #100721 (Add diagnostics lints to `rustc_type_ir` module)
 - #100731 (rustdoc: count deref and non-deref as same set of used methods)

Failed merges:

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

1 files changed, 1 insertions, 1 deletions

diff --git a/compiler/rustc_errors/src/diagnostic_builder.rs b/compiler/rustc_errors/src/diagnostic_builder.rs
index 9e68ee282e6..04159bff4ff 100644
--- a/compiler/rustc_errors/src/diagnostic_builder.rs
+++ b/compiler/rustc_errors/src/diagnostic_builder.rs
@@ -566,7 +566,7 @@ impl Drop for DiagnosticBuilderInner<'_> {
                         ),
                     ));
                     handler.emit_diagnostic(&mut self.diagnostic);
-                    panic!();
+                    panic!("error was constructed but not emitted");
                 }
             }
             // `.emit()` was previously called, or maybe we're during `.cancel()`.