ghdl_version = $(shell ghdl --version 2> /dev/null) vsim_version = $(shell vsim -version 2> /dev/null) # in case verilog is part of the build a verilog capable simulator is required ifdef verilog_srcs ifneq (${vsim_version},) include ../scripts/questa-sim.mk else $(error No HDL simulation tool found for verilog!) endif else ifneq (${vsim_version},) include ../scripts/questa-sim.mk else ifneq (${ghdl_version},) include ../scripts/ghdl.mk else $(error No HDL simulation tool found!) endif endif endif