ghdl -a --workdir=ghdl_work ghdl_work/hello.vhd
ghdl -r --workdir=ghdl_work hello
ghdl_work/hello.vhd:5:1:@0ms:(assertion note): Willkommen zu GdTI!
ghdl -a design.vhd
ghdl -a orgate.vhd
ghdl -a testbench.vhd
ghdl -r testbench --vcd=testbench.vcd
gtkwave testbench.vcd