PlatformIO
The STM32duino GitHub organization does not support issue met using PlatformIO . Only the Arduino IDE is supported. Below information are provided "as it" based on this PR #1413 from @brianredbeard. Do not hesitate to correct them.
In your project, set your environment to use the platform setting ststm32 and the framework setting arduino, e.g:
[env]
platform = ststm32
framework = arduino
Behind the scenes this will create a dependency on the ST STM32: development platform for PlatformIO (ststm32) and the framework package framework-arduinoststm32 (the PlatformIO name of this library as noted in /package.json).
This repository should not be confused with the ST STM32: development platform which is located at [https://github.com/platformio/platform-ststm32].