How to print "Hello World" to the simulator console when simulating LEON3 RTL code?

Question

GCC

There is a grlib library, a BCC compiler (sparc-elf-gcc). ModelSim simulates the grlib-gpl-1.5.0-b4164/designs/leon3mp project with make sim-run. Before that, with the help of BCC, the make soft command rebuilds the PROM loader and the systest.c test program. Objective: Use the printf C function to print something to the console during simulation. Putting the function in systest.c has no effect. In which direction to dig?