fix: Do not ICE on normalization failure of an extern static item

Author: ShoyuVanilla

compiler/rustc_hir_analysis/src/check/wfcheck.rs

@@ -1191,7 +1191,24 @@ pub(crate) fn check_static_item<'tcx>(
         let is_foreign_item = tcx.is_foreign_item(item_id);
 
         let forbid_unsized = !is_foreign_item || {
-            let tail = tcx.struct_tail_for_codegen(item_ty, wfcx.infcx.typing_env(wfcx.param_env));
+            let tail = tcx.struct_tail_raw(
+                item_ty,
+                &ObligationCause::dummy(),
+                |ty| match tcx
+                    .try_normalize_erasing_regions(wfcx.infcx.typing_env(wfcx.param_env), ty)
+                {
+                    Ok(ty) => ty,
+                    Err(e) => {
+                        tcx.dcx().span_delayed_bug(
+                            span,
+                            format!("could not normalize field type: {e:?}"),
+                        );
+                        ty
+                    }
+                },
+                || {},
+            );
+
             !matches!(tail.kind(), ty::Foreign(_))
         };
 

tests/ui/static/extern-static-normalization_failure-issue-148161.rs

@@ -0,0 +1,18 @@
+trait Trait {
+    type Assoc;
+}
+
+impl Trait for u8 {
+    type Assoc = i8;
+}
+
+struct Struct<T: Trait> {
+    member: T::Assoc,
+}
+
+unsafe extern "C" {
+    static VAR: Struct<i8>;
+    //~^ ERROR: the trait bound `i8: Trait` is not satisfied
+}
+
+fn main() {}

tests/ui/static/extern-static-normalization_failure-issue-148161.stderr

@@ -0,0 +1,20 @@
+error[E0277]: the trait bound `i8: Trait` is not satisfied
+  --> $DIR/extern-static-normalization_failure-issue-148161.rs:14:17
+   |
+LL |     static VAR: Struct<i8>;
+   |                 ^^^^^^^^^^ the trait `Trait` is not implemented for `i8`
+   |
+help: the trait `Trait` is implemented for `u8`
+  --> $DIR/extern-static-normalization_failure-issue-148161.rs:5:1
+   |
+LL | impl Trait for u8 {
+   | ^^^^^^^^^^^^^^^^^
+note: required by a bound in `Struct`
+  --> $DIR/extern-static-normalization_failure-issue-148161.rs:9:18
+   |
+LL | struct Struct<T: Trait> {
+   |                  ^^^^^ required by this bound in `Struct`
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0277`.