Multiple "expected expression before 'do'" errors

[SHoll.1]

I'm new to STM32 and trying to bring up the STM32L053-DISCO project in STM32CubeIDE. It mostly comiles fine, but has an issue with the HAL defines, such as below:

#define __HAL_RCC_GPIOA_CLK_ENABLE()  do { \

                    __IO uint32_t tmpreg; \

                    SET_BIT(RCC->IOPENR, RCC_IOPENR_GPIOAEN);\

                    /* Delay after an RCC peripheral clock enabling */ \

                    tmpreg = READ_BIT(RCC->IOPENR, RCC_IOPENR_GPIOAEN);\

                    UNUSED(tmpreg); \

                   } while(0)

I really don't see why it is being flagged as an error. I'm sure this must have been seen by someone else...

Best regards,

Stephen

[TDK]

It says *before* do, so before the use of the macro.

[SHoll.1]

One function call upp from this is:

#define __GPIOA_CLK_ENABLE __HAL_RCC_GPIOA_CLK_ENABLE

and before that, this:

#define KEY_BUTTON_GPIO_CLK_ENABLE()      __GPIOA_CLK_ENABLE()

and before that, this:

#define BUTTONx_GPIO_CLK_ENABLE(__INDEX__)   (KEY_BUTTON_GPIO_CLK_ENABLE())

and above that, this:

BUTTONx_GPIO_CLK_ENABLE(Button);

The HAL code is littered with this usage, and it is from a STM sourced project, admittedly written some ago. It must be something obvious but I just don't see what it is.

[TDK]

Perhaps you can show the code where the compiler is complaining. The code at and a few lines before __HAL_RCC_GPIOA_CLK_ENABLE is used.

[SHoll.1]

This is where the original function call is from (BUTTONx_GPIO_CLK_ENABLE(Button). It is from the BSP files for the STM32L053-DISCO eval board.

void BSP_PB_Init(Button_TypeDef Button, ButtonMode_TypeDef ButtonMode)

{

 GPIO_InitTypeDef GPIO_InitStruct;

 /* Enable the BUTTON Clock */

 BUTTONx_GPIO_CLK_ENABLE(Button);

 if (ButtonMode == BUTTON_MODE_GPIO)

 {

  /* Configure Button pin as input */

  GPIO_InitStruct.Pin = BUTTON_PIN[Button];

  GPIO_InitStruct.Mode = GPIO_MODE_INPUT;

  GPIO_InitStruct.Pull = GPIO_PULLDOWN;

  GPIO_InitStruct.Speed = GPIO_SPEED_FAST;

  HAL_GPIO_Init(BUTTON_PORT[Button], &GPIO_InitStruct);

 }

 if (ButtonMode == BUTTON_MODE_EXTI)

 {

  /* Configure Button pin as input with External interrupt */

  GPIO_InitStruct.Pin = BUTTON_PIN[Button];

  GPIO_InitStruct.Pull = GPIO_NOPULL;

  GPIO_InitStruct.Mode = GPIO_MODE_IT_FALLING;

  HAL_GPIO_Init(BUTTON_PORT[Button], &GPIO_InitStruct);

  /* Enable and set Button EXTI Interrupt to the lowest priority */

  HAL_NVIC_SetPriority((IRQn_Type)(BUTTON_IRQn[Button]), 3, 0);

  HAL_NVIC_EnableIRQ((IRQn_Type)(BUTTON_IRQn[Button]));

 }

}

[TDK]

The problem is

#define BUTTONx_GPIO_CLK_ENABLE(__INDEX__)   (KEY_BUTTON_GPIO_CLK_ENABLE())

When this expands, it puts the code you want to execute within parentheses, which leads to invalid syntax. Just replace that line with the appropriate macro, e.g.

__HAL_RCC_GPIOA_CLK_ENABLE();

[SHoll.1]

So why can't the original code work? It is example code from ST. I would expect the example code to be able to cleanly compile without issue. Is it possibly because a different compiler may have been used? There aren't any compiler dependencies listed in the original code...

[TDK]

You're probably using different HAL includes than when the code was written. My guess is that at the time, __HAL_RCC_GPIOA_CLK_ENABLE was written as something that could be evaluated, e.g. REG->CR |= VALUE, instead of its current do/while loop.

You haven't really explained where you got the code, so one can only guess.

Here's one BSP_LED_Init example online that I found which does not use the syntax you're using, and which would compile correctly.

int32_t BSP_LED_Init (Led_TypeDef Led)
{
 GPIO_InitTypeDef gpio_init_structure;
 /* Enable the GPIO_LED Clock */
 switch (Led)
 {
 case LED1:
 LED1_GPIO_CLK_ENABLE ();
 break;
 (…)
 case LEDN:
 LEDN_GPIO_CLK_ENABLE ();
 break;
 default:
 break;
}
 /* configure the GPIO_LED pin */
 gpio_init_structure.Pin = LED_PIN [Led];
 gpio_init_structure.Mode = GPIO_MODE_OUTPUT_PP;
 gpio_init_structure.Pull = GPIO_PULLUP;
 gpio_init_structure.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
 HAL_GPIO_Init (LED_PORT [Led], &gpio_init_structure);
 
 HAL_GPIO_WritePin (LED_PORT [Led], LED_PIN [Led], GPIO_PIN_RESET);
 return BSP_ERROR_NONE;
}

 Edit: I misread the code. This probably wouldn't compile either.

[SHoll.1]

Thanks for your help.

The code was downloaded from here:

https://www.st.com/en/embedded-software/stsw-stm32152.html

[SHoll.1]

Also, just build the project from STM32CubeMX for the STM32L0538-DISCO and it will try to use the same macros above.