Flash ECC error when using compiler optimization

Hello

I'm developing for RM48L952 using compiler 5.0.1.

My selftest function for the flash ECC runs fine without compiler optimizations (using CCS 5.3.0 for downloading and debugging). With compiler optimization -O3 the checks runs into flashClass2Error(). At this point  FEDACSTATUS is 0.

Thanks for help
Aedu

Here is my check function (generated with Halcogen, recommended modifications added):

void checkFlashECC(void)
{
    volatile uint32_t flashread = 0;

/* USER CODE BEGIN (63) */
    /* clear correctable error bits */
    flashWREG->FEDACSTATUS = 0x6U;
/* USER CODE END */
    
    flashWREG->FEDACCTRL1 = 0x000A060A;            
 
    flashWREG->FDIAGCTRL = 0x00050007;            
    
    flashWREG->FPAROVR = 0x00005A01; // halcogen_mod: Halcogen Bug, 0x00005401 is wrong
    
    flashWREG->FDIAGCTRL |= 0x01000000;            
    
    flashread = flashBadECC;    
    
    flashWREG->FDIAGCTRL = 0x000A0007;            

    /* this will have caused a single-bit error to be generated and corrected by CPU */
    /* single-bit error not captured in flash module */
    if (!(flashWREG->FEDACSTATUS & 0x2))        
    {
        flashClass2Error();
    }
    else
    {
        flashWREG->FEDACSTATUS = 0x2;                

        esmREG->ESTATUS1[0] = 0x40;                    

        flashWREG->FDIAGCTRL = 0x00050007;            
       
        flashWREG->FPAROVR = 0x00005A03;            
       
        flashWREG->FDIAGCTRL |= 0x01000000;            

        flashread = flashBadECC;                    
    }

/* USER CODE BEGIN (64) */
/* USER CODE END */
}