# Installation

## Inadequate versions of gcc/g++

Sometimes you may use a gcc/g++ of version < 4.8. In this way, you can still compile all the parts of TensorFlow and most of the parts of DeePMD-kit, but the i-PI driver will be disabled automatically. Or if you have a gcc/g++ of version >= 4.8, say, 7.2.0, you may choose to use it by doing

```bash
export CC=/path/to/gcc-7.2.0/bin/gcc
export CXX=/path/to/gcc-7.2.0/bin/g++
```

## Build files left in DeePMD-kit

When you try to build a second time when installing DeePMD-kit, files produced before may contribute to failure. Thus, you may clear them by

```bash
cd build
rm -r *
```

and redo the `cmake` process.
