---
myst:
  html_meta:
    description: Operator versioning in PyTorch C++ — managing backward compatibility for serialized models.
    keywords: PyTorch, C++, versioning, backward compatibility, operator, serialization
---

# Library Versioning

PyTorch provides version number macros for identifying the version of LibTorch in use.

**Example:**

```cpp
#include <torch/torch.h>
#include <iostream>

int main() {
  std::cout << "PyTorch version from parts: "
    << TORCH_VERSION_MAJOR << "."
    << TORCH_VERSION_MINOR << "."
    << TORCH_VERSION_PATCH << std::endl;
  std::cout << "PyTorch version: " << TORCH_VERSION << std::endl;
}
```

This will output something like:

```text
PyTorch version from parts: 1.8.0
PyTorch version: 1.8.0
```

```{note}

These macros are only available in PyTorch >= 1.8.0.
```

## Version Macros

- `TORCH_VERSION_MAJOR` - Major version number
- `TORCH_VERSION_MINOR` - Minor version number
- `TORCH_VERSION_PATCH` - Patch version number
- `TORCH_VERSION` - Full version string (e.g., "1.8.0")