I know I'm being too picky here, but since one of these values is stable regardless of `_WIN64`, might it be easier to read as:

```
#define REG_MSYSGIT_INSTALL_LOCAL L"SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Uninstall\\Git_is1"
#ifdef _WIN64
#define REG_MSYSGIT_INSTALL L"SOFTWARE\\Wow6432Node\\Microsoft\\Windows\\CurrentVersion\\Uninstall\\Git_is1"
#else
#define REG_MSYSGIT_INSTALL REG_MSYSGIT_INSTALL_LOCAL
#endif
```