While some of the examples include a "board.ld" style file, some of them were pointing to the libopencm3 provided chip specific ld scripts. When TOOLCHAIN_DIR has been overridden, those paths were no longer valid/correct.
------------------------------------------------------------------------------ README ------------------------------------------------------------------------------ This example program sends some characters on USART2 on the ST STM32L DISCOVERY eval board. (USART2 TX on PA2) The terminal settings for the receiving device/PC are 38400 8n1. The sending is done in a blocking way in the code, see the usart_irq example for a more elaborate USART example.