message: C linkage for stm32l4HAL target
  C linkage for output retargeting on stm32l4HAL target
diff: @@ -22,6 +22,10 @@ limitations under the License.
  extern UART_HandleTypeDef DEBUG_UART_HANDLE;
  +#ifdef __cplusplus
  + extern "C" {
  +#endif
  +
  #ifdef __GNUC__
  int __io_putchar(int ch) {
  HAL_UART_Transmit(&DEBUG_UART_HANDLE, (uint8_t *)&ch, 1, HAL_MAX_DELAY);
  @@ -36,4 +40,8 @@ int fputc(int ch, FILE *f) {
  }
  #endif /* __GNUC__ */
  -extern "C" void DebugLog(const char *s) { fprintf(stderr, "%s", s); }
  +void DebugLog(const char *s) { fprintf(stderr, "%s", s); }
  +
  +#ifdef __cplusplus
  +}
  +#endif
  