STM32F0 : correct compilation warnings

Author: jeromecoutant

targets/TARGET_STM/TARGET_STM32F0/device/stm32f0xx_hal_crc.c

@@ -421,6 +421,15 @@ uint32_t HAL_CRC_Calculate(CRC_HandleTypeDef *hcrc, uint32_t pBuffer[], uint32_t
   * @{
   */
 
+#if __GNUC__
+#    define MAY_ALIAS __attribute__ ((__may_alias__))
+#else
+#    define MAY_ALIAS
+#endif
+
+typedef __IO uint8_t  MAY_ALIAS uint8_io_t;
+typedef __IO uint16_t MAY_ALIAS uint16_io_t;
+
 /**
   * @brief  Return the CRC handle state.
   * @param  hcrc CRC handle
@@ -468,16 +477,16 @@ static uint32_t CRC_Handle_8(CRC_HandleTypeDef *hcrc, uint8_t pBuffer[], uint32_
    {
      if  (BufferLength%4U == 1U)
      {
-       *(uint8_t volatile*) (&hcrc->Instance->DR) = pBuffer[4*i];
+       *(uint8_io_t*) (&hcrc->Instance->DR) = pBuffer[4*i];
      }
      if  (BufferLength%4U == 2U)
      {
-       *(uint16_t volatile*) (&hcrc->Instance->DR) = ((uint32_t)pBuffer[4*i]<<8) | (uint32_t)pBuffer[4*i+1];
+       *(uint16_io_t*) (&hcrc->Instance->DR) = ((uint32_t)pBuffer[4*i]<<8) | (uint32_t)pBuffer[4*i+1];
      }
      if  (BufferLength%4U == 3U)
      {
-       *(uint16_t volatile*) (&hcrc->Instance->DR) = ((uint32_t)pBuffer[4*i]<<8) | (uint32_t)pBuffer[4*i+1];
-       *(uint8_t volatile*) (&hcrc->Instance->DR) = pBuffer[4*i+2];       
+       *(uint16_io_t*) (&hcrc->Instance->DR) = ((uint32_t)pBuffer[4*i]<<8) | (uint32_t)pBuffer[4*i+1];
+       *(uint8_io_t*) (&hcrc->Instance->DR) = pBuffer[4*i+2];
      }
    }
 
@@ -508,7 +517,7 @@ static uint32_t CRC_Handle_16(CRC_HandleTypeDef *hcrc, uint16_t pBuffer[], uint3
   }
   if ((BufferLength%2U) != 0U)
   {
-       *(uint16_t volatile*) (&hcrc->Instance->DR) = pBuffer[2*i]; 
+       *(uint16_io_t*) (&hcrc->Instance->DR) = pBuffer[2*i];
   }
 
   /* Return the CRC computed value */ 

targets/TARGET_STM/TARGET_STM32F0/device/stm32f0xx_ll_spi.h

@@ -1376,6 +1376,14 @@ __STATIC_INLINE void LL_SPI_TransmitData8(SPI_TypeDef *SPIx, uint8_t TxData)
   *((__IO uint8_t *)&SPIx->DR) = TxData;
 }
 
+#if __GNUC__
+#    define MAY_ALIAS __attribute__ ((__may_alias__))
+#else
+#    define MAY_ALIAS
+#endif
+
+typedef __IO uint16_t MAY_ALIAS uint16_io_t;
+
 /**
   * @brief  Write 16-Bits in the data register
   * @rmtoll DR           DR            LL_SPI_TransmitData16
@@ -1385,7 +1393,7 @@ __STATIC_INLINE void LL_SPI_TransmitData8(SPI_TypeDef *SPIx, uint8_t TxData)
   */
 __STATIC_INLINE void LL_SPI_TransmitData16(SPI_TypeDef *SPIx, uint16_t TxData)
 {
-  *((__IO uint16_t *)&SPIx->DR) = TxData;
+  *((uint16_io_t*)&SPIx->DR) = TxData;
 }
 
 /**

targets/TARGET_STM/TARGET_STM32F0/serial_device.c

@@ -48,7 +48,7 @@ UART_HandleTypeDef uart_handlers[UART_NUM];
 static uart_irq_handler irq_handler;
 
 // Defined in serial_api.c
-inline int8_t get_uart_index(UARTName uart_name);
+extern int8_t get_uart_index(UARTName uart_name);
 
 /******************************************************************************
  * INTERRUPTS HANDLING