[wasm] Fix fuzzer size calculation

test/fuzzer/wasm-compile.cc

Index: test/fuzzer/wasm-compile.cc
diff --git a/test/fuzzer/wasm-compile.cc b/test/fuzzer/wasm-compile.cc
index 8d70c1c3e2a9a96901b0124265f9cd639fe2a7df..5edac0af8b9164173e33b7867c267034ce5769da 100644
--- a/test/fuzzer/wasm-compile.cc
+++ b/test/fuzzer/wasm-compile.cc
@@ -59,7 +59,7 @@ class DataRange {
     } else {
       const size_t num_bytes = std::min(sizeof(T), size());
       T result;
-      memcpy(&result, data_, sizeof(num_bytes));
+      memcpy(&result, data_, num_bytes);
       data_ += num_bytes;
       size_ -= num_bytes;
       return result;