From 698f8c2f01ea549d77d7dc3338a12e04c11057b9 Mon Sep 17 00:00:00 2001
From: Daniel Baumann <daniel.baumann@progress-linux.org>
Date: Wed, 17 Apr 2024 14:02:58 +0200
Subject: Adding upstream version 1.64.0+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
---
 compiler/rustc_query_impl/src/values.rs | 45 +++++++++++++++++++++++++++++++++
 1 file changed, 45 insertions(+)
 create mode 100644 compiler/rustc_query_impl/src/values.rs

(limited to 'compiler/rustc_query_impl/src/values.rs')

diff --git a/compiler/rustc_query_impl/src/values.rs b/compiler/rustc_query_impl/src/values.rs
new file mode 100644
index 000000000..718a2971c
--- /dev/null
+++ b/compiler/rustc_query_impl/src/values.rs
@@ -0,0 +1,45 @@
+use super::QueryCtxt;
+use rustc_middle::ty::{self, AdtSizedConstraint, Ty};
+
+pub(super) trait Value<'tcx>: Sized {
+    fn from_cycle_error(tcx: QueryCtxt<'tcx>) -> Self;
+}
+
+impl<'tcx, T> Value<'tcx> for T {
+    default fn from_cycle_error(tcx: QueryCtxt<'tcx>) -> T {
+        tcx.sess.abort_if_errors();
+        bug!("Value::from_cycle_error called without errors");
+    }
+}
+
+impl<'tcx> Value<'tcx> for Ty<'_> {
+    fn from_cycle_error(tcx: QueryCtxt<'tcx>) -> Self {
+        // SAFETY: This is never called when `Self` is not `Ty<'tcx>`.
+        // FIXME: Represent the above fact in the trait system somehow.
+        unsafe { std::mem::transmute::<Ty<'tcx>, Ty<'_>>(tcx.ty_error()) }
+    }
+}
+
+impl<'tcx> Value<'tcx> for ty::SymbolName<'_> {
+    fn from_cycle_error(tcx: QueryCtxt<'tcx>) -> Self {
+        // SAFETY: This is never called when `Self` is not `SymbolName<'tcx>`.
+        // FIXME: Represent the above fact in the trait system somehow.
+        unsafe {
+            std::mem::transmute::<ty::SymbolName<'tcx>, ty::SymbolName<'_>>(ty::SymbolName::new(
+                *tcx, "<error>",
+            ))
+        }
+    }
+}
+
+impl<'tcx> Value<'tcx> for AdtSizedConstraint<'_> {
+    fn from_cycle_error(tcx: QueryCtxt<'tcx>) -> Self {
+        // SAFETY: This is never called when `Self` is not `AdtSizedConstraint<'tcx>`.
+        // FIXME: Represent the above fact in the trait system somehow.
+        unsafe {
+            std::mem::transmute::<AdtSizedConstraint<'tcx>, AdtSizedConstraint<'_>>(
+                AdtSizedConstraint(tcx.intern_type_list(&[tcx.ty_error()])),
+            )
+        }
+    }
+}
-- 
cgit v1.2.3