[wasm] void is not a valid type for a global.

src/wasm/module-decoder.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/wasm/module-decoder.h"
 
 #include "src/base/functional.h"
 #include "src/base/platform/platform.h"
 #include "src/macro-assembler.h"
 #include "src/objects.h"
@@ skipping 449 matching lines @@
 
   // Decodes a single global entry inside a module starting at {pc_}.
   void DecodeGlobalInModule(WasmGlobal* global) {
     global->name_offset = consume_string(&global->name_length, false);
     if (ok() &&
         !unibrow::Utf8::Validate(start_ + global->name_offset,
                                  global->name_length)) {
       error("global name is not valid utf8");
     }
     global->type = consume_local_type();
+    if (global->type == kAstStmt) {
+      error("invalid global type");
+    }
     global->offset = 0;
     global->exported = consume_u8("exported") != 0;
   }
 
   bool IsWithinLimit(uint32_t limit, uint32_t offset, uint32_t size) {
     if (offset > limit) return false;
     if ((offset + size) < offset) return false;  // overflow
     return (offset + size) <= limit;
   }
 
@@ skipping 337 matching lines @@
     decoder.consume_bytes(size);
   }
   if (decoder.more()) decoder.error("unexpected additional bytes");
 
   return decoder.toResult(std::move(table));
 }
 
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8