Fix parsing error on array.new_fixed on non-array (#7604)

Fixes #7602

Author: kripken

src/wasm/wasm-ir-builder.cpp

@@ -2213,6 +2213,9 @@ Result<> IRBuilder::makeArrayNewElem(HeapType type, Name elem) {
 
 Result<> IRBuilder::makeArrayNewFixed(HeapType type, uint32_t arity) {
   ArrayNewFixed curr(wasm.allocator);
+  if (!type.isArray()) {
+    return Err{"expected array type annotation on array.new_fixed"};
+  }
   curr.type = Type(type, NonNullable);
   curr.values.resize(arity);
   CHECK_ERR(visitArrayNewFixed(&curr));

test/lit/validation/array-new-fixed.wast

@@ -0,0 +1,12 @@
+;; RUN: not wasm-opt -all %s 2>&1 | filecheck %s
+
+;; CHECK: expected array type annotation on array.new_fixed
+
+(module
+  (type $struct (struct (field anyref)))
+
+  ;; The type here is a struct, not an array, so we error.
+  (global $struct (ref $struct) (array.new_fixed $struct 1
+    (i32.const 64)
+  ))
+)