Free RTOS parameter CHECK_FOR_STACK_OVERFLOW seems not to work

[MauFanGilaMedical]

Hello.

I bought Riverdi board and start to develop my code.

I found in FREERTOS_M7 Config parameters RTOS CHECK_FOR_STACK_OVERFLOW.

Documentation says

CHECK_FOR_STACK_OVERFLOW
Parameter Description:
FreeRTOS provides two optional mechanisms that can be used to assist in stack overflow detection and debugging.
- when CHECK_FOR_STACK_OVERFLOW is set to 1 (option1), one mechanism is used
- when CHECK_FOR_STACK_OVERFLOW is set to 2 (option2), both mechanisms are used.
If CHECK_FOR_STACK_OVERFLOW is not set to 0 (Disabled), the application must provide a stack overflow hook (or callback) function: void vApplicationStackOverflowHook( xTaskHandle xTask, signed char *pcTaskName );
The kernel will call that stack overflow hook whenever a stack overflow is detected
Note: when set to 1 or 2, a function with an empty body is generated in the freertos.c file (to be completed by the user)

So I set CHECK_FOR_STACK_OVERFLOW = 1, trigger a stack overflow by an infinite recursive and set a bkpoint in 

But when I run the code I just reach HardFault_Handler

What am I wrong ?

[TDK]

See here for how this works. It only checks when tasks are switched.

FreeRTOS stack usage and stack overflow checking - FreeRTOS™

[MauFanGilaMedical]

Ok, but I expect that if I call recursively a function without any limit as soon as far that stack will going to saturation and I expect that the FreeRTOS signal me that condition if I select one of the option available.

I am right ?

[TDK · Accepted solution]

Not in this case.

The check is done when tasks are switched which happens on the millisecond scale. If the overflow happens before then and a hard fault is produced, it will not be prevented. Calling a function recursively will overflow the stack very fast. It is not a magic solution that works all the time without limitation.

[MauFanGilaMedical]