nm not working for .wasm

```
// test_file.cc
#include
extern "C" {
int myadd(int a,int b){
int res = a+b;
res = res + 2;
return res;
}
int main(){
int res = myadd(1,2);
printf("res: %d\n",res);
}
}
```

```bash
$ clang++ test_file.cc -o test_file
$ nm test_file
no symbols
```

expect to see functions like _main, _myadd, _printf, etc.