Memory related issue with MCU startup ( __libc_init_array )

Dear Community,

I am developing firmware for STM32l476VGT using Gnu Make Builder and "Ac6 STM32 MCU GCC" Toolchain. I encounter a memory related run time error during the startup (before main) of my controller. The error occurs during the execution of the LoopFillZeroBss section:

	ldr	r3, = _ebss
	cmp	r2, r3
	bcc	FillZerobss

/* Call the clock system intitialization function.*/
    bl  SystemInit
/* Call static constructors */
    bl __libc_init_array
/* Call the application's entry point.*/
	bl	main

    b LoopForever
.size	Reset_Handler, .-Reset_Handler

 * @brief  This is the code that gets called when the processor receives an
 *         unexpected interrupt.  This simply enters an infinite loop, preserving
 *         the system state for examination by a debugger.
 * @param  None
 * @retval : None
    .section	.text.Default_Handler,"ax",%progbits
	b	Infinite_Loop
	.size	Default_Handler, .-Default_Handler

After the execution of  bl __libc_init_array I end up in the Infinite_Loop of  the Default_Handler. It is worth noting, that this error can be influenced by the amount memory which is statically allocated. In my source code file there is an array

static uint8_t array[SIZE] = {0};

If SIZE is smaller than threshold1, I can enter main() without any problems. If SIZE is between threshold1 and threshold2 (with threshold1 < threshold2) then the behaviour is as described above. If SIZE exceeds threshold2, a linker error (section '.bss' will not fit in region 'RAM') is generated (as expected).

I have the following questions:

1. What exactly happens, when 'bl __libc_init_array' is executed?

2. How could the fail of this command possibly related to the memory usage?

Any thoughts or helpful sources on this topic would be greatly appreciated as well.

Kind regards


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