编译esp_ble_mesh中onoff_client example出错

[Gargamel]

3. path to the project is longer than 90 characters.

This seems to be the reason. Move the project to C:\, no error happened.

This seems to be a bug in an older version of CCache in ESP-IDF.

Tried a newer version CCache, v4.3, no error happened. Seems it's a bug of CCache. We need to upgrade the version of CCache if needed.

[georgik]

Update: We're working on update of CMake and CCache to resolve the limitation with too long installation paths on Windows causing problem with libsodium

[georgik]

Update: Our latest tests with latest version of CMake and Ccache indicates that builds on Windows still have the problem with long paths.

Based on the research we consider this as 3rd party limitation on Windows. Please use shorter paths on Windows.
Windows Installer 2.9 was updated and it has check for too long paths to ESP-IDF and ESP-IDF Tools: https://github.com/espressif/idf-installer/pull/16