diff --git a/lib/filter/ghdl/fir_iterative.make.inc b/lib/filter/ghdl/fir_iterative.make.inc
index 51db48a..59e62bd 100644
--- a/lib/filter/ghdl/fir_iterative.make.inc
+++ b/lib/filter/ghdl/fir_iterative.make.inc
@@ -1,19 +1,23 @@
-_PKG_NAME := FIR_ITERATIVE
-FIR_ITERATIVE_ROOT := ../../..
-FIR_ITERATIVE_LIB := $(FIR_ITERATIVE_ROOT)/lib
+# -----------------------------------------------------------
+PKG_NAME := FIR_ITERATIVE
+ROOT_PATH := ../../..
+LIB_PATH := $(ROOT_PATH)/lib
+CUR_PATH := $(shell dirname $(lastword $(MAKEFILE_LIST)))
 
-_CURDIR = $(shell dirname $(lastword $(MAKEFILE_LIST)))
+# -----------------------------------------------------------
+SRCS := $(LIB_PATH)/misc/utils_pkg.vhd
+SRCS += $(LIB_PATH)/fixed/ieee_proposed/fixed_util_pkg.vhd
+SRCS += $(LIB_PATH)/filter/src/filter_pkg.vhd
+SRCS += $(LIB_PATH)/filter/src/fir_pkg.vhd
+SRCS += $(LIB_PATH)/filter/src/fir_stage_sys.vhd
+SRCS += $(LIB_PATH)/filter/src/fir_stage.vhd
+SRCS += $(LIB_PATH)/filter/src/fir_iterative.vhd
 
-_SRC := $(FIR_ITERATIVE_LIB)/misc/utils_pkg.vhd
-_SRC += $(FIR_ITERATIVE_LIB)/fixed/ieee_proposed/fixed_util_pkg.vhd
-_SRC += $(FIR_ITERATIVE_LIB)/filter/src/filter_pkg.vhd
-_SRC += $(FIR_ITERATIVE_LIB)/filter/src/fir_pkg.vhd
-_SRC += $(FIR_ITERATIVE_LIB)/filter/src/fir_stage_sys.vhd
-_SRC += $(FIR_ITERATIVE_LIB)/filter/src/fir_stage.vhd
-_SRC += $(FIR_ITERATIVE_LIB)/filter/src/fir_iterative.vhd
+# -----------------------------------------------------------
+$(PKG_NAME)_SRCS := $(addprefix $(CUR_PATH)/,$(SRCS))
 
-
-FIR_ITERATIVE_SRCS := $(addprefix $(_CURDIR)/,$(_SRC))
-
-undefine $(_SRC)
+SRCS := 
+CUR_PATH := 
+ROOT_PATH := 
+LIB_PATH := 
 
diff --git a/lib/filter/ghdl/fir_parallel.make.inc b/lib/filter/ghdl/fir_parallel.make.inc
index f561f29..5a99092 100644
--- a/lib/filter/ghdl/fir_parallel.make.inc
+++ b/lib/filter/ghdl/fir_parallel.make.inc
@@ -1,17 +1,22 @@
-_PKG_NAME := FIR_PARALLEL
-FIR_PARALLEL_ROOT := ../../..
-FIR_PARALLEL_LIB := $(FIR_PARALLEL_ROOT)/lib
+# -----------------------------------------------------------
+PKG_NAME := FIR_PARALLEL
+ROOT_PATH := ../../..
+LIB_PATH := $(ROOT_PATH)/lib
+CUR_PATH := $(shell dirname $(lastword $(MAKEFILE_LIST)))
 
-_CURDIR = $(shell dirname $(lastword $(MAKEFILE_LIST)))
+# -----------------------------------------------------------
+SRCS := $(LIB_PATH)/misc/utils_pkg.vhd
+SRCS += $(LIB_PATH)/fixed/ieee_proposed/fixed_util_pkg.vhd
+SRCS += $(LIB_PATH)/filter/src/filter_pkg.vhd
+SRCS += $(LIB_PATH)/filter/src/fir_pkg.vhd
+SRCS += $(LIB_PATH)/filter/src/fir_stage.vhd
+SRCS += $(LIB_PATH)/filter/src/fir_parallel.vhd
 
-_SRC := $(FIR_PARALLEL_LIB)/misc/utils_pkg.vhd
-_SRC += $(FIR_PARALLEL_LIB)/fixed/ieee_proposed/fixed_util_pkg.vhd
-_SRC += $(FIR_PARALLEL_LIB)/filter/src/filter_pkg.vhd
-_SRC += $(FIR_PARALLEL_LIB)/filter/src/fir_pkg.vhd
-_SRC += $(FIR_PARALLEL_LIB)/filter/src/fir_stage.vhd
-_SRC += $(FIR_PARALLEL_LIB)/filter/src/fir_parallel.vhd
+# -----------------------------------------------------------
+$(PKG_NAME)_SRCS := $(addprefix $(CUR_PATH)/,$(SRCS))
 
-FIR_PARALLEL_SRCS := $(addprefix $(_CURDIR)/,$(_SRC))
-
-undefine $(_SRC)
+SRCS := 
+CUR_PATH := 
+ROOT_PATH := 
+LIB_PATH := 
 
diff --git a/lib/filter/ghdl/fir_semi_parallel.make.inc b/lib/filter/ghdl/fir_semi_parallel.make.inc
index 870858d..3915674 100644
--- a/lib/filter/ghdl/fir_semi_parallel.make.inc
+++ b/lib/filter/ghdl/fir_semi_parallel.make.inc
@@ -1,21 +1,24 @@
-_PKG_NAME := FIR_SEMI_PARALLEL
-_ROOT := ../../..
-_LIB := $(_ROOT)/lib
+# -----------------------------------------------------------
+PKG_NAME := FIR_SEMI_PARALLEL
+ROOT_PATH := ../../..
+LIB_PATH := $(ROOT_PATH)/lib
+CUR_PATH := $(shell dirname $(lastword $(MAKEFILE_LIST)))
 
-_CURDIR = $(shell dirname $(lastword $(MAKEFILE_LIST)))
+# -----------------------------------------------------------
+SRCS := $(LIB_PATH)/misc/utils_pkg.vhd
+SRCS += $(LIB_PATH)/rams/dpram_1w1r2c_ro_sim.vhd
+SRCS += $(LIB_PATH)/fixed/ieee_proposed/fixed_util_pkg.vhd
+SRCS += $(LIB_PATH)/filter/src/filter_pkg.vhd
+SRCS += $(LIB_PATH)/filter/src/fir_pkg.vhd
+SRCS += $(LIB_PATH)/filter/src/fir_stage_sys.vhd
+SRCS += $(LIB_PATH)/filter/src/delay_line.vhd
+SRCS += $(LIB_PATH)/filter/src/fir_semi_parallel.vhd
 
-_SRC := $(_LIB)/misc/utils_pkg.vhd
-_SRC += $(_LIB)/rams/dpram_1w1r2c_ro_sim.vhd
-_SRC += $(_LIB)/fixed/ieee_proposed/fixed_util_pkg.vhd
-_SRC += $(_LIB)/filter/src/filter_pkg.vhd
-_SRC += $(_LIB)/filter/src/fir_pkg.vhd
-_SRC += $(_LIB)/filter/src/fir_stage_sys.vhd
-_SRC += $(_LIB)/filter/src/delay_line.vhd
-_SRC += $(_LIB)/filter/src/fir_semi_parallel.vhd
+# -----------------------------------------------------------
+$(PKG_NAME)_SRCS := $(addprefix $(CUR_PATH)/,$(_SRC))
 
-$(_PKG_NAME)_SRCS := $(addprefix $(_CURDIR)/,$(_SRC))
-
-undefine $(_SRC)
-undefine $(_ROOT)
-undefine $(_LIB)
+SRCS := 
+CUR_PATH := 
+ROOT_PATH := 
+LIB_PATH :=