Extend an existing platform with a local toolchain and framework


I would like to add a toolchain and a framework locally to an existing platform. How would I do that? I am doing this on Windows 10, and the PlatformIO files are stored under C:\.platformio. I want to extend the GigaDevice GD32V platform, so the files are stored under C:\.platformio\platforms\gd32v.

I read Custom Development Platforms and several forum conversations related to this topic, but it is unclear how to approach this.

Would I create a copy of the whole C:\.platformio\platforms\gd32v directory and make modifications there, so I effectively would create a new platform? That is what I understand from reading the Installation section under Custom Development Platforms .

But when I create a copy of C:\.platformio\platforms\gd32v, e.g. to C:\.platformio\platforms\gd32vllvm, and edit the "name" and "title" entries in C:\.platformio\platforms\gd32vllvm\platform.json accordingly, and then I do a platformio platform search, the new platform does not show up.

What am I doing wrong?