diff --git a/compiler/rustc_traits/src/normalize_erasing_regions.rs b/compiler/rustc_traits/src/normalize_erasing_regions.rs
index c5ebc2d26a794..6bca15e0c76b8 100644
--- a/compiler/rustc_traits/src/normalize_erasing_regions.rs
+++ b/compiler/rustc_traits/src/normalize_erasing_regions.rs
@@ -41,9 +41,9 @@ fn try_normalize_after_erasing_regions<'tcx, T: TypeFoldable<TyCtxt<'tcx>> + Par
             // fresh `InferCtxt`. If this assert does trigger, it will give
             // us a test case.
             debug_assert_eq!(normalized_value, resolved_value);
+
             let erased = infcx.tcx.erase_regions(resolved_value);
-            debug_assert!(!erased.has_infer(), "{erased:?}");
-            Ok(erased)
+            if !erased.has_infer() { Ok(erased) } else { Err(NoSolution) }
         }
         Err(NoSolution) => Err(NoSolution),
     }
diff --git a/tests/crashes/126942.rs b/tests/crashes/126942.rs
deleted file mode 100644
index e4adc8fab287e..0000000000000
--- a/tests/crashes/126942.rs
+++ /dev/null
@@ -1,11 +0,0 @@
-//@ known-bug: rust-lang/rust#126942
-struct Thing;
-
-pub trait Every {
-    type Assoc;
-}
-impl<T: ?Sized> Every for Thing {
-    type Assoc = T;
-}
-
-static I: <Thing as Every>::Assoc = 3;
diff --git a/tests/ui/layout/ice-layout-of-invalid-type-126942.rs b/tests/ui/layout/ice-layout-of-invalid-type-126942.rs
new file mode 100644
index 0000000000000..999a7496acaed
--- /dev/null
+++ b/tests/ui/layout/ice-layout-of-invalid-type-126942.rs
@@ -0,0 +1,25 @@
+// Regression test for #126942 and #127804
+
+// Tests that we do not ICE when a projection
+// type cannot be fully normalized
+
+struct Thing;
+
+pub trait Every {
+    type Assoc;
+}
+impl<T: ?Sized> Every for Thing {
+//~^ ERROR the type parameter `T` is not constrained by the impl trait, self type, or predicates
+    type Assoc = T;
+}
+
+ // The type of this static normalizes to `Infer`
+ // thanks to the `?Sized` constraint in the impl above
+static I: <Thing as Every>::Assoc = 3;
+//~^ ERROR type annotations needed
+
+fn foo(_: <Thing as Every>::Assoc) {}
+//~^ ERROR type annotations needed
+//~| ERROR type annotations needed
+
+fn main() {}
diff --git a/tests/ui/layout/ice-layout-of-invalid-type-126942.stderr b/tests/ui/layout/ice-layout-of-invalid-type-126942.stderr
new file mode 100644
index 0000000000000..db7947314678b
--- /dev/null
+++ b/tests/ui/layout/ice-layout-of-invalid-type-126942.stderr
@@ -0,0 +1,31 @@
+error[E0207]: the type parameter `T` is not constrained by the impl trait, self type, or predicates
+  --> $DIR/ice-layout-of-invalid-type-126942.rs:11:6
+   |
+LL | impl<T: ?Sized> Every for Thing {
+   |      ^ unconstrained type parameter
+
+error[E0283]: type annotations needed
+  --> $DIR/ice-layout-of-invalid-type-126942.rs:18:11
+   |
+LL | static I: <Thing as Every>::Assoc = 3;
+   |           ^^^^^^^^^^^^^^^^^^^^^^^ cannot infer type for type parameter `T`
+   |
+   = note: cannot satisfy `_: Sync`
+   = note: shared static variables must have a type that implements `Sync`
+
+error[E0282]: type annotations needed
+  --> $DIR/ice-layout-of-invalid-type-126942.rs:21:11
+   |
+LL | fn foo(_: <Thing as Every>::Assoc) {}
+   |           ^^^^^^^^^^^^^^^^^^^^^^^ cannot infer type for type parameter `T`
+
+error[E0282]: type annotations needed
+  --> $DIR/ice-layout-of-invalid-type-126942.rs:21:8
+   |
+LL | fn foo(_: <Thing as Every>::Assoc) {}
+   |        ^ cannot infer type for type parameter `T`
+
+error: aborting due to 4 previous errors
+
+Some errors have detailed explanations: E0207, E0282, E0283.
+For more information about an error, try `rustc --explain E0207`.