关于A20硬件编码例子的编译问题。

[wei你]

OS：ubuntu 16.10
编译器：arm-linux-gnueabi-gcc-4.7 ,arm-linux-gnueabi-g++-4.7
用A20的开发板，做视频硬件编码库，里面有几个例子，并有Makefile:
CPP = arm-linux-gnueabi-g++
STRIP = arm-linux-gnueabi-strip
AR = arm-linux-gnueabi-ar
CEDARX_CHIP_VERSION = A20

TARGET=encodeDemo
BUILDPATH=.

SRCDIRS:=.

CFLAGS =-Wall -O0 -g -ldl

INCLUDES:=$(foreach dir,$(SRCDIRS),-I$(dir)) \
-I../include \
-I../lib \
-I../include/include_system \
-I../include/include_vencoder \
-I../include/include_camera \
-I../include/include_platform/CHIP_$(CEDARX_CHIP_VERSION)/disp \
-I../include/include_platform/CHIP_$(CEDARX_CHIP_VERSION)

SRCCS=$(foreach dir,$(SRCDIRS),$(wildcard $(dir)/*.c))

LIBOBJ=$(addprefix $(BUILDPATH)/, $(addsuffix .o, $(basename $(SRCCS))))

LDFLAGS=-lpthread -lvencoder -ldl -L../lib/$(CEDARX_CHIP_VERSION) -L/usr/arm-linux-gnueabi/lib

all: $(TARGET)

$(BUILDPATH)/%.o:%.c
$(CC) $(CFLAGS) ${INCLUDES} $(LDFLAGS) -o $@ -c $<

$(TARGET):$(LIBOBJ)
$(CPP) $(LDFLAGS) -o $@ $^

clean:
rm -f $(TARGET) $(LIBOBJ)

这是make执行的编译命令
arm-linux-gnueabi-gcc -Wall -O0 -g -ldl -I. -I../include -I../lib -I../include/include_system -I../include/include_vencoder -I../include/include_camera -I../include/include_platform/CHIP_A20/disp -I../include/include_platform/CHIP_A20 -o main.o -c main.c
编译除了有几个警告外没什么问题。但连接它是用的arm-linux-gnueabi-g++做的，然后出现了很多未定义的引用。请问各位，这是怎么回事？应该怎么修改？

arm-linux-gnueabi-g++ -lpthread -lvencoder -ldl -L../lib/A20 -L/usr/arm-linux-gnueabi/lib -o encodeDemo main.o

main.o：在函数‘main’中：
/home/ww/soft/linux-codec-release-V1.2/linux-codec-release-V1.2/encDemo/main.c:151：对‘cedarx_hardware_init’未定义的引用
/home/ww/soft/linux-codec-release-V1.2/linux-codec-release-V1.2/encDemo/main.c:153：对‘cedarvEncInit’未定义的引用
/home/ww/soft/linux-codec-release-V1.2/linux-codec-release-V1.2/encDemo/main.c:165：对‘cedarvEncExit’未定义的引用
/home/ww/soft/linux-codec-release-V1.2/linux-codec-release-V1.2/encDemo/main.c:168：对‘cedarx_hardware_exit’未定义的引用
/home/ww/soft/linux-codec-release-V1.2/linux-codec-release-V1.2/encDemo/main.c:177：对‘cedarvEncExit’未定义的引用
/home/ww/soft/linux-codec-release-V1.2/linux-codec-release-V1.2/encDemo/main.c:180：对‘cedarx_hardware_exit’未定义的引用
/home/ww/soft/linux-codec-release-V1.2/linux-codec-release-V1.2/encDemo/main.c:191：对‘pthread_create’未定义的引用
/home/ww/soft/linux-codec-release-V1.2/linux-codec-release-V1.2/encDemo/main.c:197：对‘pthread_create’未定义的引用
/home/ww/soft/linux-codec-release-V1.2/linux-codec-release-V1.2/encDemo/main.c:203：对‘pthread_join’未定义的引用
/home/ww/soft/linux-codec-release-V1.2/linux-codec-release-V1.2/encDemo/main.c:207：对‘pthread_join’未定义的引用
/home/ww/soft/linux-codec-release-V1.2/linux-codec-release-V1.2/encDemo/main.c:211：对‘cedarvEncExit’未定义的引用
/home/ww/soft/linux-codec-release-V1.2/linux-codec-release-V1.2/encDemo/main.c:214：对‘cedarx_hardware_exit’未定义的引用
collect2: 错误： ld 返回 1
Makefile:35: recipe for target 'encodeDemo' failed
make: *** [encodeDemo] Error 1