diff --git a/src/passes/Print.cpp b/src/passes/Print.cpp
index 8a1c72999ee..d4adeaa4636 100644
--- a/src/passes/Print.cpp
+++ b/src/passes/Print.cpp
@@ -321,7 +321,8 @@ struct PrintSExpression : public UnifiedExpressionVisitor<PrintSExpression> {
   void printUnreachableReplacement(Expression* curr);
   bool maybePrintUnreachableReplacement(Expression* curr, Type type);
   void visitRefCast(RefCast* curr) {
-    if (!maybePrintUnreachableReplacement(curr, curr->type)) {
+    if ((curr->desc && curr->desc->type != Type::unreachable) ||
+        !maybePrintUnreachableReplacement(curr, curr->type)) {
       visitExpression(curr);
     }
   }
@@ -2224,7 +2225,20 @@ struct PrintExpressionContents
     } else {
       printMedium(o, "ref.cast ");
     }
-    printType(curr->type);
+    if (curr->type != Type::unreachable) {
+      printType(curr->type);
+    } else {
+      // We can still recover a valid result type from the type of the
+      // descriptor.
+      auto described = curr->desc->type.getHeapType().getDescribedType();
+      if (described) {
+        printType(
+          Type(*described, NonNullable, curr->desc->type.getExactness()));
+      } else {
+        // Invalid, so it doesn't matter what we print.
+        printType(Type::unreachable);
+      }
+    }
   }
   void visitRefGetDesc(RefGetDesc* curr) {
     printMedium(o, "ref.get_desc ");
diff --git a/src/wasm/wasm-validator.cpp b/src/wasm/wasm-validator.cpp
index 9ed4027df94..576cc476934 100644
--- a/src/wasm/wasm-validator.cpp
+++ b/src/wasm/wasm-validator.cpp
@@ -2944,6 +2944,18 @@ void FunctionValidator::visitRefTest(RefTest* curr) {
 void FunctionValidator::visitRefCast(RefCast* curr) {
   shouldBeTrue(
     getModule()->features.hasGC(), curr, "ref.cast requires gc [--enable-gc]");
+
+  // Require descriptors to be valid even if the ref is unreachable.
+  if (curr->desc && curr->desc->type != Type::unreachable) {
+    auto descType = curr->desc->type;
+    bool isNull = descType.isNull();
+    bool isDescriptor =
+      descType.isRef() && descType.getHeapType().getDescribedType();
+    shouldBeTrue(isNull || isDescriptor,
+                 curr,
+                 "ref.cast_desc descriptor must be a descriptor reference");
+  }
+
   if (curr->type == Type::unreachable) {
     return;
   }
@@ -3006,11 +3018,7 @@ void FunctionValidator::visitRefCast(RefCast* curr) {
   }
 
   auto described = descriptor.getDescribedType();
-  if (!shouldBeTrue(bool(described),
-                    curr,
-                    "ref.cast_desc descriptor should have a described type")) {
-    return;
-  }
+  assert(described && "already checked descriptor");
   shouldBeEqual(*described,
                 curr->type.getHeapType(),
                 curr,
diff --git a/test/gtest/validator.cpp b/test/gtest/validator.cpp
index 99d5878ae19..ec7caa295d1 100644
--- a/test/gtest/validator.cpp
+++ b/test/gtest/validator.cpp
@@ -22,6 +22,7 @@
 #include "support/string.h"
 #include "wasm-binary.h"
 #include "wasm-builder.h"
+#include "wasm-features.h"
 #include "wasm-validator.h"
 #include "gtest/gtest.h"
 
@@ -65,3 +66,27 @@ TEST(ValidatorTest, ReturnUnreachable) {
     WasmValidator::FlagValues::Globally | WasmValidator::FlagValues::Quiet;
   EXPECT_FALSE(WasmValidator{}.validate(func.get(), module, flags));
 }
+
+TEST(ValidatorTest, UnreachableCastDesc) {
+  // The parser will error trying to parse a ref.cast_desc with a non-matching
+  // descriptor type, so we must construct the IR directly to test the
+  // validator.
+  Module module;
+  module.features = FeatureSet::All;
+  Builder builder(module);
+
+  auto func = builder.makeFunction(
+    "func",
+    {},
+    Signature(Type::none, Type::none),
+    {},
+    builder.makeDrop(builder.makeRefCast(builder.makeUnreachable(),
+                                         builder.makeStructNew(Struct{}, {}),
+                                         Type::unreachable)));
+
+  ASSERT_EQ(func->body->type, Type(Type::unreachable));
+
+  auto flags =
+    WasmValidator::FlagValues::Globally | WasmValidator::FlagValues::Quiet;
+  EXPECT_FALSE(WasmValidator{}.validate(func.get(), module, flags));
+}
diff --git a/test/lit/basic/custom-descriptors.wast b/test/lit/basic/custom-descriptors.wast
index f1d302dbad5..8e0892f2d40 100644
--- a/test/lit/basic/custom-descriptors.wast
+++ b/test/lit/basic/custom-descriptors.wast
@@ -41,23 +41,39 @@
 
   (rec
 
-    ;; CHECK-TEXT:      (type $6 (func (param anyref (ref null $describing))))
+    ;; CHECK-TEXT:      (type $6 (func))
 
-    ;; CHECK-TEXT:      (type $7 (func (result anyref)))
+    ;; CHECK-TEXT:      (type $7 (func (param anyref (ref null $describing))))
 
-    ;; CHECK-TEXT:      (type $8 (func (param anyref (ref null (exact $middle))) (result (ref null (exact $described)))))
+    ;; CHECK-TEXT:      (type $8 (func (param (ref null $describing))))
 
-    ;; CHECK-TEXT:      (type $9 (func (result (ref (exact $pair)))))
+    ;; CHECK-TEXT:      (type $9 (func (result anyref)))
+
+    ;; CHECK-TEXT:      (type $10 (func (param (ref null $middle)) (result anyref)))
+
+    ;; CHECK-TEXT:      (type $11 (func (param (ref null (exact $middle))) (result anyref)))
+
+    ;; CHECK-TEXT:      (type $12 (func (param anyref (ref null (exact $middle))) (result (ref null (exact $described)))))
+
+    ;; CHECK-TEXT:      (type $13 (func (result (ref (exact $pair)))))
 
     ;; CHECK-TEXT:      (rec
     ;; CHECK-TEXT-NEXT:  (type $shared-described (shared (descriptor $shared-describing (struct))))
-    ;; CHECK-BIN:      (type $6 (func (param anyref (ref null $describing))))
+    ;; CHECK-BIN:      (type $6 (func))
+
+    ;; CHECK-BIN:      (type $7 (func (param anyref (ref null $describing))))
+
+    ;; CHECK-BIN:      (type $8 (func (param (ref null $describing))))
 
-    ;; CHECK-BIN:      (type $7 (func (result anyref)))
+    ;; CHECK-BIN:      (type $9 (func (result anyref)))
 
-    ;; CHECK-BIN:      (type $8 (func (param anyref (ref null (exact $middle))) (result (ref null (exact $described)))))
+    ;; CHECK-BIN:      (type $10 (func (param (ref null $middle)) (result anyref)))
 
-    ;; CHECK-BIN:      (type $9 (func (result (ref (exact $pair)))))
+    ;; CHECK-BIN:      (type $11 (func (param (ref null (exact $middle))) (result anyref)))
+
+    ;; CHECK-BIN:      (type $12 (func (param anyref (ref null (exact $middle))) (result (ref null (exact $described)))))
+
+    ;; CHECK-BIN:      (type $13 (func (result (ref (exact $pair)))))
 
     ;; CHECK-BIN:      (rec
     ;; CHECK-BIN-NEXT:  (type $shared-described (shared (descriptor $shared-describing (struct))))
@@ -69,18 +85,14 @@
 
 
 
-  ;; CHECK-TEXT:      (type $12 (func (param (ref null $described) (ref null (exact $middle)))))
-
-  ;; CHECK-TEXT:      (type $13 (func))
+  ;; CHECK-TEXT:      (type $16 (func (param (ref null $described) (ref null (exact $middle)))))
 
-  ;; CHECK-TEXT:      (type $14 (func (param (ref any) (ref null $middle)) (result (ref null $described))))
+  ;; CHECK-TEXT:      (type $17 (func (param (ref any) (ref null $middle)) (result (ref null $described))))
 
   ;; CHECK-TEXT:      (global $g (ref null $described) (ref.null none))
-  ;; CHECK-BIN:      (type $12 (func (param (ref null $described) (ref null (exact $middle)))))
+  ;; CHECK-BIN:      (type $16 (func (param (ref null $described) (ref null (exact $middle)))))
 
-  ;; CHECK-BIN:      (type $13 (func))
-
-  ;; CHECK-BIN:      (type $14 (func (param (ref any) (ref null $middle)) (result (ref null $described))))
+  ;; CHECK-BIN:      (type $17 (func (param (ref any) (ref null $middle)) (result (ref null $described))))
 
   ;; CHECK-BIN:      (global $g (ref null $described) (ref.null none))
   (global $g (ref null $described) (ref.null none))
@@ -88,7 +100,7 @@
   ;; CHECK-BIN:      (global $shared (ref null $shared-describing) (ref.null (shared none)))
   (global $shared (ref null $shared-describing) (ref.null (shared none)))
 
-  ;; CHECK-TEXT:      (func $ref-get-desc (type $12) (param $described (ref null $described)) (param $middle-exact (ref null (exact $middle)))
+  ;; CHECK-TEXT:      (func $ref-get-desc (type $16) (param $described (ref null $described)) (param $middle-exact (ref null (exact $middle)))
   ;; CHECK-TEXT-NEXT:  (drop
   ;; CHECK-TEXT-NEXT:   (block $l1 (result (ref $middle))
   ;; CHECK-TEXT-NEXT:    (ref.get_desc $described
@@ -104,7 +116,7 @@
   ;; CHECK-TEXT-NEXT:   )
   ;; CHECK-TEXT-NEXT:  )
   ;; CHECK-TEXT-NEXT: )
-  ;; CHECK-BIN:      (func $ref-get-desc (type $12) (param $described (ref null $described)) (param $middle-exact (ref null (exact $middle)))
+  ;; CHECK-BIN:      (func $ref-get-desc (type $16) (param $described (ref null $described)) (param $middle-exact (ref null (exact $middle)))
   ;; CHECK-BIN-NEXT:  (drop
   ;; CHECK-BIN-NEXT:   (block (result (ref $middle))
   ;; CHECK-BIN-NEXT:    (ref.get_desc $described
@@ -137,7 +149,7 @@
     )
   )
 
-  ;; CHECK-TEXT:      (func $ref-get-desc-null (type $13)
+  ;; CHECK-TEXT:      (func $ref-get-desc-null (type $6)
   ;; CHECK-TEXT-NEXT:  (drop
   ;; CHECK-TEXT-NEXT:   (block ;; (replaces unreachable RefGetDesc we can't emit)
   ;; CHECK-TEXT-NEXT:    (drop
@@ -147,7 +159,7 @@
   ;; CHECK-TEXT-NEXT:   )
   ;; CHECK-TEXT-NEXT:  )
   ;; CHECK-TEXT-NEXT: )
-  ;; CHECK-BIN:      (func $ref-get-desc-null (type $13)
+  ;; CHECK-BIN:      (func $ref-get-desc-null (type $6)
   ;; CHECK-BIN-NEXT:  (drop
   ;; CHECK-BIN-NEXT:   (ref.null none)
   ;; CHECK-BIN-NEXT:  )
@@ -163,7 +175,7 @@
     )
   )
 
-  ;; CHECK-TEXT:      (func $br-on-cast-desc (type $6) (param $any anyref) (param $descriptor (ref null $describing))
+  ;; CHECK-TEXT:      (func $br-on-cast-desc (type $7) (param $any anyref) (param $descriptor (ref null $describing))
   ;; CHECK-TEXT-NEXT:  (drop
   ;; CHECK-TEXT-NEXT:   (block $l (result (ref null $middle))
   ;; CHECK-TEXT-NEXT:    (drop
@@ -176,7 +188,7 @@
   ;; CHECK-TEXT-NEXT:   )
   ;; CHECK-TEXT-NEXT:  )
   ;; CHECK-TEXT-NEXT: )
-  ;; CHECK-BIN:      (func $br-on-cast-desc (type $6) (param $any anyref) (param $descriptor (ref null $describing))
+  ;; CHECK-BIN:      (func $br-on-cast-desc (type $7) (param $any anyref) (param $descriptor (ref null $describing))
   ;; CHECK-BIN-NEXT:  (drop
   ;; CHECK-BIN-NEXT:   (block $block (result (ref null $middle))
   ;; CHECK-BIN-NEXT:    (drop
@@ -201,7 +213,7 @@
     )
   )
 
-  ;; CHECK-TEXT:      (func $br-on-cast-desc-fail (type $6) (param $any anyref) (param $descriptor (ref null $describing))
+  ;; CHECK-TEXT:      (func $br-on-cast-desc-fail (type $7) (param $any anyref) (param $descriptor (ref null $describing))
   ;; CHECK-TEXT-NEXT:  (drop
   ;; CHECK-TEXT-NEXT:   (block $l (result anyref)
   ;; CHECK-TEXT-NEXT:    (br_on_cast_desc_fail $l anyref (ref null $middle)
@@ -211,7 +223,7 @@
   ;; CHECK-TEXT-NEXT:   )
   ;; CHECK-TEXT-NEXT:  )
   ;; CHECK-TEXT-NEXT: )
-  ;; CHECK-BIN:      (func $br-on-cast-desc-fail (type $6) (param $any anyref) (param $descriptor (ref null $describing))
+  ;; CHECK-BIN:      (func $br-on-cast-desc-fail (type $7) (param $any anyref) (param $descriptor (ref null $describing))
   ;; CHECK-BIN-NEXT:  (drop
   ;; CHECK-BIN-NEXT:   (block $block (result anyref)
   ;; CHECK-BIN-NEXT:    (br_on_cast_desc_fail $block anyref (ref null $middle)
@@ -232,6 +244,134 @@
     )
   )
 
+  ;; CHECK-TEXT:      (func $br-on-cast-desc-unreachable (type $6)
+  ;; CHECK-TEXT-NEXT:  (drop
+  ;; CHECK-TEXT-NEXT:   (block $l (result (ref null $middle))
+  ;; CHECK-TEXT-NEXT:    (block ;; (replaces unreachable BrOn we can't emit)
+  ;; CHECK-TEXT-NEXT:     (drop
+  ;; CHECK-TEXT-NEXT:      (unreachable)
+  ;; CHECK-TEXT-NEXT:     )
+  ;; CHECK-TEXT-NEXT:     (drop
+  ;; CHECK-TEXT-NEXT:      (unreachable)
+  ;; CHECK-TEXT-NEXT:     )
+  ;; CHECK-TEXT-NEXT:     (unreachable)
+  ;; CHECK-TEXT-NEXT:    )
+  ;; CHECK-TEXT-NEXT:    (unreachable)
+  ;; CHECK-TEXT-NEXT:   )
+  ;; CHECK-TEXT-NEXT:  )
+  ;; CHECK-TEXT-NEXT: )
+  ;; CHECK-BIN:      (func $br-on-cast-desc-unreachable (type $6)
+  ;; CHECK-BIN-NEXT:  (drop
+  ;; CHECK-BIN-NEXT:   (block (result (ref null $middle))
+  ;; CHECK-BIN-NEXT:    (unreachable)
+  ;; CHECK-BIN-NEXT:   )
+  ;; CHECK-BIN-NEXT:  )
+  ;; CHECK-BIN-NEXT: )
+  (func $br-on-cast-desc-unreachable
+    (drop
+      (block $l (result (ref null $middle))
+        (br_on_cast_desc $l anyref (ref null $middle)
+          (unreachable)
+        )
+        (unreachable)
+      )
+    )
+  )
+
+    ;; CHECK-TEXT:      (func $br-on-cast-desc-fail-unreachable (type $6)
+    ;; CHECK-TEXT-NEXT:  (drop
+    ;; CHECK-TEXT-NEXT:   (block $l (result (ref null $middle))
+    ;; CHECK-TEXT-NEXT:    (block ;; (replaces unreachable BrOn we can't emit)
+    ;; CHECK-TEXT-NEXT:     (drop
+    ;; CHECK-TEXT-NEXT:      (unreachable)
+    ;; CHECK-TEXT-NEXT:     )
+    ;; CHECK-TEXT-NEXT:     (drop
+    ;; CHECK-TEXT-NEXT:      (unreachable)
+    ;; CHECK-TEXT-NEXT:     )
+    ;; CHECK-TEXT-NEXT:     (unreachable)
+    ;; CHECK-TEXT-NEXT:    )
+    ;; CHECK-TEXT-NEXT:    (unreachable)
+    ;; CHECK-TEXT-NEXT:   )
+    ;; CHECK-TEXT-NEXT:  )
+    ;; CHECK-TEXT-NEXT: )
+    ;; CHECK-BIN:      (func $br-on-cast-desc-fail-unreachable (type $6)
+    ;; CHECK-BIN-NEXT:  (drop
+    ;; CHECK-BIN-NEXT:   (block (result (ref null $middle))
+    ;; CHECK-BIN-NEXT:    (unreachable)
+    ;; CHECK-BIN-NEXT:   )
+    ;; CHECK-BIN-NEXT:  )
+    ;; CHECK-BIN-NEXT: )
+    (func $br-on-cast-desc-fail-unreachable
+    (drop
+      (block $l (result (ref null $middle))
+        (br_on_cast_desc_fail $l anyref (ref null $middle)
+          (unreachable)
+        )
+        (unreachable)
+      )
+    )
+  )
+
+  ;; CHECK-TEXT:      (func $br-on-cast-desc-unreachable-desc (type $8) (param $descriptor (ref null $describing))
+  ;; CHECK-TEXT-NEXT:  (drop
+  ;; CHECK-TEXT-NEXT:   (block $l (result (ref null $middle))
+  ;; CHECK-TEXT-NEXT:    (br_on_cast_desc $l (ref null $middle) (ref null $middle)
+  ;; CHECK-TEXT-NEXT:     (unreachable)
+  ;; CHECK-TEXT-NEXT:     (local.get $descriptor)
+  ;; CHECK-TEXT-NEXT:    )
+  ;; CHECK-TEXT-NEXT:    (unreachable)
+  ;; CHECK-TEXT-NEXT:   )
+  ;; CHECK-TEXT-NEXT:  )
+  ;; CHECK-TEXT-NEXT: )
+  ;; CHECK-BIN:      (func $br-on-cast-desc-unreachable-desc (type $8) (param $descriptor (ref null $describing))
+  ;; CHECK-BIN-NEXT:  (drop
+  ;; CHECK-BIN-NEXT:   (block (result (ref null $middle))
+  ;; CHECK-BIN-NEXT:    (unreachable)
+  ;; CHECK-BIN-NEXT:   )
+  ;; CHECK-BIN-NEXT:  )
+  ;; CHECK-BIN-NEXT: )
+  (func $br-on-cast-desc-unreachable-desc (param $descriptor (ref null $describing))
+    (drop
+      (block $l (result (ref null $middle))
+        (br_on_cast_desc $l anyref (ref null $middle)
+          (unreachable)
+          (local.get $descriptor)
+        )
+        (unreachable)
+      )
+    )
+  )
+
+  ;; CHECK-TEXT:      (func $br-on-cast-desc-fail-unreachable-desc (type $8) (param $descriptor (ref null $describing))
+  ;; CHECK-TEXT-NEXT:  (drop
+  ;; CHECK-TEXT-NEXT:   (block $l (result (ref null $middle))
+  ;; CHECK-TEXT-NEXT:    (br_on_cast_desc_fail $l (ref null $middle) (ref null $middle)
+  ;; CHECK-TEXT-NEXT:     (unreachable)
+  ;; CHECK-TEXT-NEXT:     (local.get $descriptor)
+  ;; CHECK-TEXT-NEXT:    )
+  ;; CHECK-TEXT-NEXT:    (unreachable)
+  ;; CHECK-TEXT-NEXT:   )
+  ;; CHECK-TEXT-NEXT:  )
+  ;; CHECK-TEXT-NEXT: )
+  ;; CHECK-BIN:      (func $br-on-cast-desc-fail-unreachable-desc (type $8) (param $descriptor (ref null $describing))
+  ;; CHECK-BIN-NEXT:  (drop
+  ;; CHECK-BIN-NEXT:   (block (result (ref null $middle))
+  ;; CHECK-BIN-NEXT:    (unreachable)
+  ;; CHECK-BIN-NEXT:   )
+  ;; CHECK-BIN-NEXT:  )
+  ;; CHECK-BIN-NEXT: )
+  (func $br-on-cast-desc-fail-unreachable-desc (param $descriptor (ref null $describing))
+    (drop
+      (block $l (result (ref null $middle))
+        (br_on_cast_desc_fail $l anyref (ref null $middle)
+          (unreachable)
+          (local.get $descriptor)
+        )
+        (unreachable)
+      )
+    )
+  )
+
   ;; CHECK-TEXT:      (func $br-on-cast-desc-null (type $3) (param $0 anyref) (result anyref)
   ;; CHECK-TEXT-NEXT:  (block $label (result anyref)
   ;; CHECK-TEXT-NEXT:   (block ;; (replaces unreachable BrOn we can't emit)
@@ -290,7 +430,7 @@
     )
   )
 
-  ;; CHECK-TEXT:      (func $ref-cast-desc-null-unreachable (type $7) (result anyref)
+  ;; CHECK-TEXT:      (func $ref-cast-desc-null-unreachable (type $9) (result anyref)
   ;; CHECK-TEXT-NEXT:  (block ;; (replaces unreachable RefCast we can't emit)
   ;; CHECK-TEXT-NEXT:   (drop
   ;; CHECK-TEXT-NEXT:    (unreachable)
@@ -301,7 +441,7 @@
   ;; CHECK-TEXT-NEXT:   (unreachable)
   ;; CHECK-TEXT-NEXT:  )
   ;; CHECK-TEXT-NEXT: )
-  ;; CHECK-BIN:      (func $ref-cast-desc-null-unreachable (type $7) (result anyref)
+  ;; CHECK-BIN:      (func $ref-cast-desc-null-unreachable (type $9) (result anyref)
   ;; CHECK-BIN-NEXT:  (unreachable)
   ;; CHECK-BIN-NEXT: )
   (func $ref-cast-desc-null-unreachable (result anyref)
@@ -309,6 +449,70 @@
     (ref.cast_desc (ref null $described))
   )
 
+  ;; CHECK-TEXT:      (func $ref-cast-desc-null-unreachable-ref (type $10) (param $descriptor (ref null $middle)) (result anyref)
+  ;; CHECK-TEXT-NEXT:  (ref.cast_desc (ref $described)
+  ;; CHECK-TEXT-NEXT:   (unreachable)
+  ;; CHECK-TEXT-NEXT:   (local.get $descriptor)
+  ;; CHECK-TEXT-NEXT:  )
+  ;; CHECK-TEXT-NEXT: )
+  ;; CHECK-BIN:      (func $ref-cast-desc-null-unreachable-ref (type $10) (param $descriptor (ref null $middle)) (result anyref)
+  ;; CHECK-BIN-NEXT:  (unreachable)
+  ;; CHECK-BIN-NEXT: )
+  (func $ref-cast-desc-null-unreachable-ref (param $descriptor (ref null $middle)) (result anyref)
+    (ref.cast_desc (ref null $described)
+      (unreachable)
+      (local.get $descriptor)
+    )
+  )
+
+  ;; CHECK-TEXT:      (func $ref-cast-desc-unreachable-ref (type $10) (param $descriptor (ref null $middle)) (result anyref)
+  ;; CHECK-TEXT-NEXT:  (ref.cast_desc (ref $described)
+  ;; CHECK-TEXT-NEXT:   (unreachable)
+  ;; CHECK-TEXT-NEXT:   (local.get $descriptor)
+  ;; CHECK-TEXT-NEXT:  )
+  ;; CHECK-TEXT-NEXT: )
+  ;; CHECK-BIN:      (func $ref-cast-desc-unreachable-ref (type $10) (param $descriptor (ref null $middle)) (result anyref)
+  ;; CHECK-BIN-NEXT:  (unreachable)
+  ;; CHECK-BIN-NEXT: )
+  (func $ref-cast-desc-unreachable-ref (param $descriptor (ref null $middle)) (result anyref)
+    (ref.cast_desc (ref $described)
+      (unreachable)
+      (local.get $descriptor)
+    )
+  )
+
+  ;; CHECK-TEXT:      (func $ref-cast-desc-exact-null-unreachable-ref (type $11) (param $descriptor (ref null (exact $middle))) (result anyref)
+  ;; CHECK-TEXT-NEXT:  (ref.cast_desc (ref (exact $described))
+  ;; CHECK-TEXT-NEXT:   (unreachable)
+  ;; CHECK-TEXT-NEXT:   (local.get $descriptor)
+  ;; CHECK-TEXT-NEXT:  )
+  ;; CHECK-TEXT-NEXT: )
+  ;; CHECK-BIN:      (func $ref-cast-desc-exact-null-unreachable-ref (type $11) (param $descriptor (ref null (exact $middle))) (result anyref)
+  ;; CHECK-BIN-NEXT:  (unreachable)
+  ;; CHECK-BIN-NEXT: )
+  (func $ref-cast-desc-exact-null-unreachable-ref (param $descriptor (ref null (exact $middle))) (result anyref)
+    (ref.cast_desc (ref null (exact $described))
+      (unreachable)
+      (local.get $descriptor)
+    )
+  )
+
+  ;; CHECK-TEXT:      (func $ref-cast-desc-exact-unreachable-ref (type $11) (param $descriptor (ref null (exact $middle))) (result anyref)
+  ;; CHECK-TEXT-NEXT:  (ref.cast_desc (ref (exact $described))
+  ;; CHECK-TEXT-NEXT:   (unreachable)
+  ;; CHECK-TEXT-NEXT:   (local.get $descriptor)
+  ;; CHECK-TEXT-NEXT:  )
+  ;; CHECK-TEXT-NEXT: )
+  ;; CHECK-BIN:      (func $ref-cast-desc-exact-unreachable-ref (type $11) (param $descriptor (ref null (exact $middle))) (result anyref)
+  ;; CHECK-BIN-NEXT:  (unreachable)
+  ;; CHECK-BIN-NEXT: )
+  (func $ref-cast-desc-exact-unreachable-ref (param $descriptor (ref null (exact $middle))) (result anyref)
+    (ref.cast_desc (ref (exact $described))
+      (unreachable)
+      (local.get $descriptor)
+    )
+  )
+
   ;; CHECK-TEXT:      (func $ref-cast-desc-null-null (type $3) (param $0 anyref) (result anyref)
   ;; CHECK-TEXT-NEXT:  (block ;; (replaces unreachable RefCast we can't emit)
   ;; CHECK-TEXT-NEXT:   (drop
@@ -336,13 +540,13 @@
     )
   )
 
-  ;; CHECK-TEXT:      (func $ref-cast-desc-null-exact (type $8) (param $any anyref) (param $middle (ref null (exact $middle))) (result (ref null (exact $described)))
+  ;; CHECK-TEXT:      (func $ref-cast-desc-null-exact (type $12) (param $any anyref) (param $middle (ref null (exact $middle))) (result (ref null (exact $described)))
   ;; CHECK-TEXT-NEXT:  (ref.cast_desc (ref null (exact $described))
   ;; CHECK-TEXT-NEXT:   (local.get $any)
   ;; CHECK-TEXT-NEXT:   (local.get $middle)
   ;; CHECK-TEXT-NEXT:  )
   ;; CHECK-TEXT-NEXT: )
-  ;; CHECK-BIN:      (func $ref-cast-desc-null-exact (type $8) (param $any anyref) (param $middle (ref null (exact $middle))) (result (ref null (exact $described)))
+  ;; CHECK-BIN:      (func $ref-cast-desc-null-exact (type $12) (param $any anyref) (param $middle (ref null (exact $middle))) (result (ref null (exact $described)))
   ;; CHECK-BIN-NEXT:  (ref.cast_desc (ref null (exact $described))
   ;; CHECK-BIN-NEXT:   (local.get $any)
   ;; CHECK-BIN-NEXT:   (local.get $middle)
@@ -356,7 +560,7 @@
     )
   )
 
-  ;; CHECK-TEXT:      (func $ref-cast-desc-nn-unreachable (type $7) (result anyref)
+  ;; CHECK-TEXT:      (func $ref-cast-desc-nn-unreachable (type $9) (result anyref)
   ;; CHECK-TEXT-NEXT:  (block ;; (replaces unreachable RefCast we can't emit)
   ;; CHECK-TEXT-NEXT:   (drop
   ;; CHECK-TEXT-NEXT:    (unreachable)
@@ -367,7 +571,7 @@
   ;; CHECK-TEXT-NEXT:   (unreachable)
   ;; CHECK-TEXT-NEXT:  )
   ;; CHECK-TEXT-NEXT: )
-  ;; CHECK-BIN:      (func $ref-cast-desc-nn-unreachable (type $7) (result anyref)
+  ;; CHECK-BIN:      (func $ref-cast-desc-nn-unreachable (type $9) (result anyref)
   ;; CHECK-BIN-NEXT:  (unreachable)
   ;; CHECK-BIN-NEXT: )
   (func $ref-cast-desc-nn-unreachable (result anyref)
@@ -402,13 +606,13 @@
     )
   )
 
-  ;; CHECK-TEXT:      (func $ref-cast-desc-nn-exact (type $8) (param $any anyref) (param $middle (ref null (exact $middle))) (result (ref null (exact $described)))
+  ;; CHECK-TEXT:      (func $ref-cast-desc-nn-exact (type $12) (param $any anyref) (param $middle (ref null (exact $middle))) (result (ref null (exact $described)))
   ;; CHECK-TEXT-NEXT:  (ref.cast_desc (ref (exact $described))
   ;; CHECK-TEXT-NEXT:   (local.get $any)
   ;; CHECK-TEXT-NEXT:   (local.get $middle)
   ;; CHECK-TEXT-NEXT:  )
   ;; CHECK-TEXT-NEXT: )
-  ;; CHECK-BIN:      (func $ref-cast-desc-nn-exact (type $8) (param $any anyref) (param $middle (ref null (exact $middle))) (result (ref null (exact $described)))
+  ;; CHECK-BIN:      (func $ref-cast-desc-nn-exact (type $12) (param $any anyref) (param $middle (ref null (exact $middle))) (result (ref null (exact $described)))
   ;; CHECK-BIN-NEXT:  (ref.cast_desc (ref (exact $described))
   ;; CHECK-BIN-NEXT:   (local.get $any)
   ;; CHECK-BIN-NEXT:   (local.get $middle)
@@ -422,13 +626,13 @@
     )
   )
 
-  ;; CHECK-TEXT:      (func $ref-cast-desc-nn-to-null (type $14) (param $any-nn (ref any)) (param $middle (ref null $middle)) (result (ref null $described))
+  ;; CHECK-TEXT:      (func $ref-cast-desc-nn-to-null (type $17) (param $any-nn (ref any)) (param $middle (ref null $middle)) (result (ref null $described))
   ;; CHECK-TEXT-NEXT:  (ref.cast_desc (ref $described)
   ;; CHECK-TEXT-NEXT:   (local.get $any-nn)
   ;; CHECK-TEXT-NEXT:   (local.get $middle)
   ;; CHECK-TEXT-NEXT:  )
   ;; CHECK-TEXT-NEXT: )
-  ;; CHECK-BIN:      (func $ref-cast-desc-nn-to-null (type $14) (param $any-nn (ref any)) (param $middle (ref null $middle)) (result (ref null $described))
+  ;; CHECK-BIN:      (func $ref-cast-desc-nn-to-null (type $17) (param $any-nn (ref any)) (param $middle (ref null $middle)) (result (ref null $described))
   ;; CHECK-BIN-NEXT:  (ref.cast_desc (ref $described)
   ;; CHECK-BIN-NEXT:   (local.get $any-nn)
   ;; CHECK-BIN-NEXT:   (local.get $middle)
@@ -441,14 +645,14 @@
     )
   )
 
-  ;; CHECK-TEXT:      (func $struct-new (type $9) (result (ref (exact $pair)))
+  ;; CHECK-TEXT:      (func $struct-new (type $13) (result (ref (exact $pair)))
   ;; CHECK-TEXT-NEXT:  (struct.new $pair
   ;; CHECK-TEXT-NEXT:   (i32.const 0)
   ;; CHECK-TEXT-NEXT:   (i64.const 1)
   ;; CHECK-TEXT-NEXT:   (struct.new_default $pair.desc)
   ;; CHECK-TEXT-NEXT:  )
   ;; CHECK-TEXT-NEXT: )
-  ;; CHECK-BIN:      (func $struct-new (type $9) (result (ref (exact $pair)))
+  ;; CHECK-BIN:      (func $struct-new (type $13) (result (ref (exact $pair)))
   ;; CHECK-BIN-NEXT:  (struct.new $pair
   ;; CHECK-BIN-NEXT:   (i32.const 0)
   ;; CHECK-BIN-NEXT:   (i64.const 1)
@@ -463,12 +667,12 @@
     )
   )
 
-  ;; CHECK-TEXT:      (func $struct-new-default (type $9) (result (ref (exact $pair)))
+  ;; CHECK-TEXT:      (func $struct-new-default (type $13) (result (ref (exact $pair)))
   ;; CHECK-TEXT-NEXT:  (struct.new_default $pair
   ;; CHECK-TEXT-NEXT:   (struct.new_default $pair.desc)
   ;; CHECK-TEXT-NEXT:  )
   ;; CHECK-TEXT-NEXT: )
-  ;; CHECK-BIN:      (func $struct-new-default (type $9) (result (ref (exact $pair)))
+  ;; CHECK-BIN:      (func $struct-new-default (type $13) (result (ref (exact $pair)))
   ;; CHECK-BIN-NEXT:  (struct.new_default $pair
   ;; CHECK-BIN-NEXT:   (struct.new_default $pair.desc)
   ;; CHECK-BIN-NEXT:  )
@@ -494,30 +698,36 @@
 
 ;; CHECK-BIN-NODEBUG:       (type $5 (describes $4 (struct)))
 
-;; CHECK-BIN-NODEBUG:      (type $6 (func (param anyref (ref null $2))))
+;; CHECK-BIN-NODEBUG:      (type $6 (func))
 
-;; CHECK-BIN-NODEBUG:      (type $7 (func (result anyref)))
+;; CHECK-BIN-NODEBUG:      (type $7 (func (param anyref (ref null $2))))
 
-;; CHECK-BIN-NODEBUG:      (type $8 (func (param anyref (ref null (exact $1))) (result (ref null (exact $0)))))
+;; CHECK-BIN-NODEBUG:      (type $8 (func (param (ref null $2))))
 
-;; CHECK-BIN-NODEBUG:      (type $9 (func (result (ref (exact $4)))))
+;; CHECK-BIN-NODEBUG:      (type $9 (func (result anyref)))
 
-;; CHECK-BIN-NODEBUG:      (rec
-;; CHECK-BIN-NODEBUG-NEXT:  (type $10 (shared (descriptor $11 (struct))))
+;; CHECK-BIN-NODEBUG:      (type $10 (func (param (ref null $1)) (result anyref)))
+
+;; CHECK-BIN-NODEBUG:      (type $11 (func (param (ref null (exact $1))) (result anyref)))
 
-;; CHECK-BIN-NODEBUG:       (type $11 (shared (describes $10 (struct))))
+;; CHECK-BIN-NODEBUG:      (type $12 (func (param anyref (ref null (exact $1))) (result (ref null (exact $0)))))
+
+;; CHECK-BIN-NODEBUG:      (type $13 (func (result (ref (exact $4)))))
+
+;; CHECK-BIN-NODEBUG:      (rec
+;; CHECK-BIN-NODEBUG-NEXT:  (type $14 (shared (descriptor $15 (struct))))
 
-;; CHECK-BIN-NODEBUG:      (type $12 (func (param (ref null $0) (ref null (exact $1)))))
+;; CHECK-BIN-NODEBUG:       (type $15 (shared (describes $14 (struct))))
 
-;; CHECK-BIN-NODEBUG:      (type $13 (func))
+;; CHECK-BIN-NODEBUG:      (type $16 (func (param (ref null $0) (ref null (exact $1)))))
 
-;; CHECK-BIN-NODEBUG:      (type $14 (func (param (ref any) (ref null $1)) (result (ref null $0))))
+;; CHECK-BIN-NODEBUG:      (type $17 (func (param (ref any) (ref null $1)) (result (ref null $0))))
 
 ;; CHECK-BIN-NODEBUG:      (global $global$0 (ref null $0) (ref.null none))
 
-;; CHECK-BIN-NODEBUG:      (global $global$1 (ref null $11) (ref.null (shared none)))
+;; CHECK-BIN-NODEBUG:      (global $global$1 (ref null $15) (ref.null (shared none)))
 
-;; CHECK-BIN-NODEBUG:      (func $0 (type $12) (param $0 (ref null $0)) (param $1 (ref null (exact $1)))
+;; CHECK-BIN-NODEBUG:      (func $0 (type $16) (param $0 (ref null $0)) (param $1 (ref null (exact $1)))
 ;; CHECK-BIN-NODEBUG-NEXT:  (drop
 ;; CHECK-BIN-NODEBUG-NEXT:   (block (result (ref $1))
 ;; CHECK-BIN-NODEBUG-NEXT:    (ref.get_desc $0
@@ -534,7 +744,7 @@
 ;; CHECK-BIN-NODEBUG-NEXT:  )
 ;; CHECK-BIN-NODEBUG-NEXT: )
 
-;; CHECK-BIN-NODEBUG:      (func $1 (type $13)
+;; CHECK-BIN-NODEBUG:      (func $1 (type $6)
 ;; CHECK-BIN-NODEBUG-NEXT:  (drop
 ;; CHECK-BIN-NODEBUG-NEXT:   (ref.null none)
 ;; CHECK-BIN-NODEBUG-NEXT:  )
@@ -543,7 +753,7 @@
 ;; CHECK-BIN-NODEBUG-NEXT:  )
 ;; CHECK-BIN-NODEBUG-NEXT: )
 
-;; CHECK-BIN-NODEBUG:      (func $2 (type $6) (param $0 anyref) (param $1 (ref null $2))
+;; CHECK-BIN-NODEBUG:      (func $2 (type $7) (param $0 anyref) (param $1 (ref null $2))
 ;; CHECK-BIN-NODEBUG-NEXT:  (drop
 ;; CHECK-BIN-NODEBUG-NEXT:   (block $block (result (ref null $1))
 ;; CHECK-BIN-NODEBUG-NEXT:    (drop
@@ -557,7 +767,7 @@
 ;; CHECK-BIN-NODEBUG-NEXT:  )
 ;; CHECK-BIN-NODEBUG-NEXT: )
 
-;; CHECK-BIN-NODEBUG:      (func $3 (type $6) (param $0 anyref) (param $1 (ref null $2))
+;; CHECK-BIN-NODEBUG:      (func $3 (type $7) (param $0 anyref) (param $1 (ref null $2))
 ;; CHECK-BIN-NODEBUG-NEXT:  (drop
 ;; CHECK-BIN-NODEBUG-NEXT:   (block $block (result anyref)
 ;; CHECK-BIN-NODEBUG-NEXT:    (br_on_cast_desc_fail $block anyref (ref null $1)
@@ -568,7 +778,39 @@
 ;; CHECK-BIN-NODEBUG-NEXT:  )
 ;; CHECK-BIN-NODEBUG-NEXT: )
 
-;; CHECK-BIN-NODEBUG:      (func $4 (type $3) (param $0 anyref) (result anyref)
+;; CHECK-BIN-NODEBUG:      (func $4 (type $6)
+;; CHECK-BIN-NODEBUG-NEXT:  (drop
+;; CHECK-BIN-NODEBUG-NEXT:   (block (result (ref null $1))
+;; CHECK-BIN-NODEBUG-NEXT:    (unreachable)
+;; CHECK-BIN-NODEBUG-NEXT:   )
+;; CHECK-BIN-NODEBUG-NEXT:  )
+;; CHECK-BIN-NODEBUG-NEXT: )
+
+;; CHECK-BIN-NODEBUG:      (func $5 (type $6)
+;; CHECK-BIN-NODEBUG-NEXT:  (drop
+;; CHECK-BIN-NODEBUG-NEXT:   (block (result (ref null $1))
+;; CHECK-BIN-NODEBUG-NEXT:    (unreachable)
+;; CHECK-BIN-NODEBUG-NEXT:   )
+;; CHECK-BIN-NODEBUG-NEXT:  )
+;; CHECK-BIN-NODEBUG-NEXT: )
+
+;; CHECK-BIN-NODEBUG:      (func $6 (type $8) (param $0 (ref null $2))
+;; CHECK-BIN-NODEBUG-NEXT:  (drop
+;; CHECK-BIN-NODEBUG-NEXT:   (block (result (ref null $1))
+;; CHECK-BIN-NODEBUG-NEXT:    (unreachable)
+;; CHECK-BIN-NODEBUG-NEXT:   )
+;; CHECK-BIN-NODEBUG-NEXT:  )
+;; CHECK-BIN-NODEBUG-NEXT: )
+
+;; CHECK-BIN-NODEBUG:      (func $7 (type $8) (param $0 (ref null $2))
+;; CHECK-BIN-NODEBUG-NEXT:  (drop
+;; CHECK-BIN-NODEBUG-NEXT:   (block (result (ref null $1))
+;; CHECK-BIN-NODEBUG-NEXT:    (unreachable)
+;; CHECK-BIN-NODEBUG-NEXT:   )
+;; CHECK-BIN-NODEBUG-NEXT:  )
+;; CHECK-BIN-NODEBUG-NEXT: )
+
+;; CHECK-BIN-NODEBUG:      (func $8 (type $3) (param $0 anyref) (result anyref)
 ;; CHECK-BIN-NODEBUG-NEXT:  (drop
 ;; CHECK-BIN-NODEBUG-NEXT:   (ref.null none)
 ;; CHECK-BIN-NODEBUG-NEXT:  )
@@ -578,7 +820,7 @@
 ;; CHECK-BIN-NODEBUG-NEXT:  (unreachable)
 ;; CHECK-BIN-NODEBUG-NEXT: )
 
-;; CHECK-BIN-NODEBUG:      (func $5 (type $3) (param $0 anyref) (result anyref)
+;; CHECK-BIN-NODEBUG:      (func $9 (type $3) (param $0 anyref) (result anyref)
 ;; CHECK-BIN-NODEBUG-NEXT:  (drop
 ;; CHECK-BIN-NODEBUG-NEXT:   (ref.null none)
 ;; CHECK-BIN-NODEBUG-NEXT:  )
@@ -588,11 +830,27 @@
 ;; CHECK-BIN-NODEBUG-NEXT:  (unreachable)
 ;; CHECK-BIN-NODEBUG-NEXT: )
 
-;; CHECK-BIN-NODEBUG:      (func $6 (type $7) (result anyref)
+;; CHECK-BIN-NODEBUG:      (func $10 (type $9) (result anyref)
+;; CHECK-BIN-NODEBUG-NEXT:  (unreachable)
+;; CHECK-BIN-NODEBUG-NEXT: )
+
+;; CHECK-BIN-NODEBUG:      (func $11 (type $10) (param $0 (ref null $1)) (result anyref)
+;; CHECK-BIN-NODEBUG-NEXT:  (unreachable)
+;; CHECK-BIN-NODEBUG-NEXT: )
+
+;; CHECK-BIN-NODEBUG:      (func $12 (type $10) (param $0 (ref null $1)) (result anyref)
+;; CHECK-BIN-NODEBUG-NEXT:  (unreachable)
+;; CHECK-BIN-NODEBUG-NEXT: )
+
+;; CHECK-BIN-NODEBUG:      (func $13 (type $11) (param $0 (ref null (exact $1))) (result anyref)
+;; CHECK-BIN-NODEBUG-NEXT:  (unreachable)
+;; CHECK-BIN-NODEBUG-NEXT: )
+
+;; CHECK-BIN-NODEBUG:      (func $14 (type $11) (param $0 (ref null (exact $1))) (result anyref)
 ;; CHECK-BIN-NODEBUG-NEXT:  (unreachable)
 ;; CHECK-BIN-NODEBUG-NEXT: )
 
-;; CHECK-BIN-NODEBUG:      (func $7 (type $3) (param $0 anyref) (result anyref)
+;; CHECK-BIN-NODEBUG:      (func $15 (type $3) (param $0 anyref) (result anyref)
 ;; CHECK-BIN-NODEBUG-NEXT:  (drop
 ;; CHECK-BIN-NODEBUG-NEXT:   (ref.null none)
 ;; CHECK-BIN-NODEBUG-NEXT:  )
@@ -602,18 +860,18 @@
 ;; CHECK-BIN-NODEBUG-NEXT:  (unreachable)
 ;; CHECK-BIN-NODEBUG-NEXT: )
 
-;; CHECK-BIN-NODEBUG:      (func $8 (type $8) (param $0 anyref) (param $1 (ref null (exact $1))) (result (ref null (exact $0)))
+;; CHECK-BIN-NODEBUG:      (func $16 (type $12) (param $0 anyref) (param $1 (ref null (exact $1))) (result (ref null (exact $0)))
 ;; CHECK-BIN-NODEBUG-NEXT:  (ref.cast_desc (ref null (exact $0))
 ;; CHECK-BIN-NODEBUG-NEXT:   (local.get $0)
 ;; CHECK-BIN-NODEBUG-NEXT:   (local.get $1)
 ;; CHECK-BIN-NODEBUG-NEXT:  )
 ;; CHECK-BIN-NODEBUG-NEXT: )
 
-;; CHECK-BIN-NODEBUG:      (func $9 (type $7) (result anyref)
+;; CHECK-BIN-NODEBUG:      (func $17 (type $9) (result anyref)
 ;; CHECK-BIN-NODEBUG-NEXT:  (unreachable)
 ;; CHECK-BIN-NODEBUG-NEXT: )
 
-;; CHECK-BIN-NODEBUG:      (func $10 (type $3) (param $0 anyref) (result anyref)
+;; CHECK-BIN-NODEBUG:      (func $18 (type $3) (param $0 anyref) (result anyref)
 ;; CHECK-BIN-NODEBUG-NEXT:  (drop
 ;; CHECK-BIN-NODEBUG-NEXT:   (ref.null none)
 ;; CHECK-BIN-NODEBUG-NEXT:  )
@@ -623,21 +881,21 @@
 ;; CHECK-BIN-NODEBUG-NEXT:  (unreachable)
 ;; CHECK-BIN-NODEBUG-NEXT: )
 
-;; CHECK-BIN-NODEBUG:      (func $11 (type $8) (param $0 anyref) (param $1 (ref null (exact $1))) (result (ref null (exact $0)))
+;; CHECK-BIN-NODEBUG:      (func $19 (type $12) (param $0 anyref) (param $1 (ref null (exact $1))) (result (ref null (exact $0)))
 ;; CHECK-BIN-NODEBUG-NEXT:  (ref.cast_desc (ref (exact $0))
 ;; CHECK-BIN-NODEBUG-NEXT:   (local.get $0)
 ;; CHECK-BIN-NODEBUG-NEXT:   (local.get $1)
 ;; CHECK-BIN-NODEBUG-NEXT:  )
 ;; CHECK-BIN-NODEBUG-NEXT: )
 
-;; CHECK-BIN-NODEBUG:      (func $12 (type $14) (param $0 (ref any)) (param $1 (ref null $1)) (result (ref null $0))
+;; CHECK-BIN-NODEBUG:      (func $20 (type $17) (param $0 (ref any)) (param $1 (ref null $1)) (result (ref null $0))
 ;; CHECK-BIN-NODEBUG-NEXT:  (ref.cast_desc (ref $0)
 ;; CHECK-BIN-NODEBUG-NEXT:   (local.get $0)
 ;; CHECK-BIN-NODEBUG-NEXT:   (local.get $1)
 ;; CHECK-BIN-NODEBUG-NEXT:  )
 ;; CHECK-BIN-NODEBUG-NEXT: )
 
-;; CHECK-BIN-NODEBUG:      (func $13 (type $9) (result (ref (exact $4)))
+;; CHECK-BIN-NODEBUG:      (func $21 (type $13) (result (ref (exact $4)))
 ;; CHECK-BIN-NODEBUG-NEXT:  (struct.new $4
 ;; CHECK-BIN-NODEBUG-NEXT:   (i32.const 0)
 ;; CHECK-BIN-NODEBUG-NEXT:   (i64.const 1)
@@ -645,7 +903,7 @@
 ;; CHECK-BIN-NODEBUG-NEXT:  )
 ;; CHECK-BIN-NODEBUG-NEXT: )
 
-;; CHECK-BIN-NODEBUG:      (func $14 (type $9) (result (ref (exact $4)))
+;; CHECK-BIN-NODEBUG:      (func $22 (type $13) (result (ref (exact $4)))
 ;; CHECK-BIN-NODEBUG-NEXT:  (struct.new_default $4
 ;; CHECK-BIN-NODEBUG-NEXT:   (struct.new_default $5)
 ;; CHECK-BIN-NODEBUG-NEXT:  )