From CARM to Realview

Hello,
i have a few experience with CARM.
But now i try to make a change to Realview.
BLINKY example runs, but when i add a printf programm stops bevor reaching main.
The programm ends in a endlessloop after having done a SWI 0xAB
Here you can see result of step by step debuging:

0x00081800  B508      PUSH      {R3,LR}
0x00081802  4669      MOV       R1,SP
0x00081804  9000      STR       R0,[SP,#0x0000]
0x00081806  2003      MOV       R0,#0x03
0x00081808  DFAB      SWI       0xAB

   116: SWI_Handler     B       SWI_Handler

0x00080044  EAFFFFFE  B         0x00080044

WHY? My programm is "molto semplice" and similar stuff has worked in CARM a hundred times:

int main (void)
{
        PLL_init();
        RS232_init(115200);
        printf("Hello this is my first test of Realview");
        while(1);
}

I'am despaired, who can help?