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

src/wasm/module-decoder.cc

Index: src/wasm/module-decoder.cc
diff --git a/src/wasm/module-decoder.cc b/src/wasm/module-decoder.cc
index cf855af21b2b6c7820d80e106be5bda2dfc2372e..c47aa351a3409209e7425989dda2314db8cbe815 100644
--- a/src/wasm/module-decoder.cc
+++ b/src/wasm/module-decoder.cc
@@ -467,6 +467,9 @@ class ModuleDecoder : public Decoder {
       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;
   }