![Undefined reference to `_open` when trying to compile v2-dev branch for SAM3X8E/Duet085 · Issue #188 · Duet3D/RepRapFirmware · GitHub Undefined reference to `_open` when trying to compile v2-dev branch for SAM3X8E/Duet085 · Issue #188 · Duet3D/RepRapFirmware · GitHub](https://user-images.githubusercontent.com/5753253/42085825-bc9aac64-7b91-11e8-87f3-612dc540810a.png)
Undefined reference to `_open` when trying to compile v2-dev branch for SAM3X8E/Duet085 · Issue #188 · Duet3D/RepRapFirmware · GitHub
![c - .\Objects\Usart.axf: Error: L6218E: Undefined symbol HAL_NVIC_SetPriority (referred from stm32f4xx_hal.o) - Stack Overflow c - .\Objects\Usart.axf: Error: L6218E: Undefined symbol HAL_NVIC_SetPriority (referred from stm32f4xx_hal.o) - Stack Overflow](https://i.stack.imgur.com/SgsbK.png)
c - .\Objects\Usart.axf: Error: L6218E: Undefined symbol HAL_NVIC_SetPriority (referred from stm32f4xx_hal.o) - Stack Overflow
![File inclusion error - Undefined reference to app_uart_get - Nordic Q&A - Nordic DevZone - Nordic DevZone File inclusion error - Undefined reference to app_uart_get - Nordic Q&A - Nordic DevZone - Nordic DevZone](https://devzone.nordicsemi.com/resized-image/__size/640x480/__key/support-attachments/beef5d1b77644c448dabff31668f3a47-0797f4b598a24d308453d817c1e2c3bf/WhatsApp-Image-2019_2D00_07_2D00_06-at-11.44.27-AM.jpeg)
File inclusion error - Undefined reference to app_uart_get - Nordic Q&A - Nordic DevZone - Nordic DevZone
![Getting undefined reference when compiling for board stm32f4discovery · Issue #53 · micro-ROS/NuttX · GitHub Getting undefined reference when compiling for board stm32f4discovery · Issue #53 · micro-ROS/NuttX · GitHub](https://user-images.githubusercontent.com/12581592/90961358-d96ca180-e4da-11ea-8a6d-5813ddef4575.png)