我有下面的makefile，虽然它可以很好地构建各个对象文件，但我无法用它将对象链接到最终的可执行文件中。它在构建主目标时同时输出(.text+0x0): multiple definition和(.text+0x44): undefined reference to错误。
# Set compiler
CC = gcc
# Include headers
INC_HDR := -I. -IAPI/core -IAPI/platform
# Define final executable
EXE := driver
# List source
SRC := $(wildcard API/core/*.c)
$(wildcard API/platform/*.c)
main.c
# List headers
HDR := $(wildcard API/core/*.h)
$(wildcard API/platform/*.h)
# Derive objects
OBJ := $(patsubst %.c, %.o, $(SRC))
# Set flags
CPPFLAGS := $(INC_HDR) -MMD -MP # -I is a preprocessor flag, not a compiler flag -MMD -MP
CFLAGS := -Wall # some warnings about bad code
LDFLAGS := -L. # -L is a linker flag
LDLIBS := -lm # Left empty if no libs are needed
.PHONY: all clean
all: $(EXE)
$(EXE): $(OBJ)
@echo Linking $@
$(CC) $(CPPFLAGS) $(CFLAGS) $(LDLIBS) $^ -o $@
$(OBJ): $(SRC) $(HDR)
@echo Building $@
$(CC) $(CPPFLAGS) $(CFLAGS) -c $< -o $@
clean:
@find . -type f -name '*.o' -delete
@find . -type f -name '*.d' -delete
这个问题与其他帖子非常接近，但到目前为止我还没能找到问题所在。
根据要求，make clean all的输出为：
Building API/core/VL53L1X_calibration.o
gcc -I. -IAPI/core -IAPI/platform -MMD -MP -Wall -c API/core/VL53L1X_calibration.c -o API/core/VL53L1X_calibration.o
Building API/core/VL53L1X_api.o
gcc -I. -IAPI/core -IAPI/platform -MMD -MP -Wall -c API/core/VL53L1X_calibration.c -o API/core/VL53L1X_api.o
Building API/platform/vl53l1_platform.o
gcc -I. -IAPI/core -IAPI/platform -MMD -MP -Wall -c API/core/VL53L1X_calibration.c -o API/platform/vl53l1_platform.o
Building main.o
gcc -I. -IAPI/core -IAPI/platform -MMD -MP -Wall -c API/core/VL53L1X_calibration.c -o main.o
Linking driver
gcc -I. -IAPI/core -IAPI/platform -MMD -MP -Wall -lm API/core/VL53L1X_calibration.o API/core/VL53L1X_api.o API/platform/vl53l1_platform.o main.o -o driver
API/core/VL53L1X_api.o: In function `VL53L1X_CalibrateOffset':
VL53L1X_calibration.c:(.text+0x0): multiple definition of `VL53L1X_CalibrateOffset'
API/core/VL53L1X_calibration.o:VL53L1X_calibration.c:(.text+0x0): first defined here
API/core/VL53L1X_api.o: In function `VL53L1X_CalibrateXtalk':
VL53L1X_calibration.c:(.text+0x170): multiple definition of `VL53L1X_CalibrateXtalk'
API/core/VL53L1X_calibration.o:VL53L1X_calibration.c:(.text+0x170): first defined here
API/platform/vl53l1_platform.o: In function `VL53L1X_CalibrateOffset':
VL53L1X_calibration.c:(.text+0x0): multiple definition of `VL53L1X_CalibrateOffset'
API/core/VL53L1X_calibration.o:VL53L1X_calibration.c:(.text+0x0): first defined here
API/platform/vl53l1_platform.o: In function `VL53L1X_CalibrateXtalk':
VL53L1X_calibration.c:(.text+0x170): multiple definition of `VL53L1X_CalibrateXtalk'
API/core/VL53L1X_calibration.o:VL53L1X_calibration.c:(.text+0x170): first defined here
main.o: In function `VL53L1X_CalibrateOffset':
VL53L1X_calibration.c:(.text+0x0): multiple definition of `VL53L1X_CalibrateOffset'
API/core/VL53L1X_calibration.o:VL53L1X_calibration.c:(.text+0x0): first defined here
main.o: In function `VL53L1X_CalibrateXtalk':
VL53L1X_calibration.c:(.text+0x170): multiple definition of `VL53L1X_CalibrateXtalk'
API/core/VL53L1X_calibration.o:VL53L1X_calibration.c:(.text+0x170): first defined here
/usr/lib/gcc/x86_64-linux-gnu/7/../../../x86_64-linux-gnu/Scrt1.o: In function `_start':
(.text+0x20): undefined reference to `main'
API/core/VL53L1X_calibration.o: In function `VL53L1X_CalibrateOffset':
VL53L1X_calibration.c:(.text+0x44): undefined reference to `VL53L1_WrWord'
VL53L1X_calibration.c:(.text+0x5c): undefined reference to `VL53L1_WrWord'
VL53L1X_calibration.c:(.text+0x74): undefined reference to `VL53L1_WrWord'
VL53L1X_calibration.c:(.text+0x82): undefined reference to `VL53L1X_StartRanging'
VL53L1X_calibration.c:(.text+0xa3): undefined reference to `VL53L1X_CheckForDataReady'
VL53L1X_calibration.c:(.text+0xc0): undefined reference to `VL53L1X_GetDistance'
VL53L1X_calibration.c:(.text+0xce): undefined reference to `VL53L1X_ClearInterrupt'
VL53L1X_calibration.c:(.text+0xfa): undefined reference to `VL53L1X_StopRanging'
VL53L1X_calibration.c:(.text+0x14f): undefined reference to `VL53L1_WrWord'
API/core/VL53L1X_calibration.o: In function `VL53L1X_CalibrateXtalk':
VL53L1X_calibration.c:(.text+0x1cf): undefined reference to `VL53L1_WrWord'
VL53L1X_calibration.c:(.text+0x1dd): undefined reference to `VL53L1X_StartRanging'
VL53L1X_calibration.c:(.text+0x201): undefined reference to `VL53L1X_CheckForDataReady'
VL53L1X_calibration.c:(.text+0x21e): undefined reference to `VL53L1X_GetSignalRate'
VL53L1X_calibration.c:(.text+0x233): undefined reference to `VL53L1X_GetDistance'
VL53L1X_calibration.c:(.text+0x241): undefined reference to `VL53L1X_ClearInterrupt'
VL53L1X_calibration.c:(.text+0x26f): undefined reference to `VL53L1X_GetSpadNb'
VL53L1X_calibration.c:(.text+0x2c3): undefined reference to `VL53L1X_StopRanging'
VL53L1X_calibration.c:(.text+0x376): undefined reference to `VL53L1_WrWord'
API/core/VL53L1X_api.o: In function `VL53L1X_CalibrateOffset':
VL53L1X_calibration.c:(.text+0x44): undefined reference to `VL53L1_WrWord'
VL53L1X_calibration.c:(.text+0x5c): undefined reference to `VL53L1_WrWord'
VL53L1X_calibration.c:(.text+0x74): undefined reference to `VL53L1_WrWord'
VL53L1X_calibration.c:(.text+0x82): undefined reference to `VL53L1X_StartRanging'
VL53L1X_calibration.c:(.text+0xa3): undefined reference to `VL53L1X_CheckForDataReady'
VL53L1X_calibration.c:(.text+0xc0): undefined reference to `VL53L1X_GetDistance'
VL53L1X_calibration.c:(.text+0xce): undefined reference to `VL53L1X_ClearInterrupt'
VL53L1X_calibration.c:(.text+0xfa): undefined reference to `VL53L1X_StopRanging'
VL53L1X_calibration.c:(.text+0x14f): undefined reference to `VL53L1_WrWord'
API/core/VL53L1X_api.o: In function `VL53L1X_CalibrateXtalk':
VL53L1X_calibration.c:(.text+0x1cf): undefined reference to `VL53L1_WrWord'
VL53L1X_calibration.c:(.text+0x1dd): undefined reference to `VL53L1X_StartRanging'
VL53L1X_calibration.c:(.text+0x201): undefined reference to `VL53L1X_CheckForDataReady'
VL53L1X_calibration.c:(.text+0x21e): undefined reference to `VL53L1X_GetSignalRate'
VL53L1X_calibration.c:(.text+0x233): undefined reference to `VL53L1X_GetDistance'
VL53L1X_calibration.c:(.text+0x241): undefined reference to `VL53L1X_ClearInterrupt'
VL53L1X_calibration.c:(.text+0x26f): undefined reference to `VL53L1X_GetSpadNb'
VL53L1X_calibration.c:(.text+0x2c3): undefined reference to `VL53L1X_StopRanging'
VL53L1X_calibration.c:(.text+0x376): undefined reference to `VL53L1_WrWord'
API/platform/vl53l1_platform.o: In function `VL53L1X_CalibrateOffset':
VL53L1X_calibration.c:(.text+0x44): undefined reference to `VL53L1_WrWord'
VL53L1X_calibration.c:(.text+0x5c): undefined reference to `VL53L1_WrWord'
VL53L1X_calibration.c:(.text+0x74): undefined reference to `VL53L1_WrWord'
VL53L1X_calibration.c:(.text+0x82): undefined reference to `VL53L1X_StartRanging'
VL53L1X_calibration.c:(.text+0xa3): undefined reference to `VL53L1X_CheckForDataReady'
VL53L1X_calibration.c:(.text+0xc0): undefined reference to `VL53L1X_GetDistance'
VL53L1X_calibration.c:(.text+0xce): undefined reference to `VL53L1X_ClearInterrupt'
VL53L1X_calibration.c:(.text+0xfa): undefined reference to `VL53L1X_StopRanging'
VL53L1X_calibration.c:(.text+0x14f): undefined reference to `VL53L1_WrWord'
API/platform/vl53l1_platform.o: In function `VL53L1X_CalibrateXtalk':
VL53L1X_calibration.c:(.text+0x1cf): undefined reference to `VL53L1_WrWord'
VL53L1X_calibration.c:(.text+0x1dd): undefined reference to `VL53L1X_StartRanging'
VL53L1X_calibration.c:(.text+0x201): undefined reference to `VL53L1X_CheckForDataReady'
VL53L1X_calibration.c:(.text+0x21e): undefined reference to `VL53L1X_GetSignalRate'
VL53L1X_calibration.c:(.text+0x233): undefined reference to `VL53L1X_GetDistance'
VL53L1X_calibration.c:(.text+0x241): undefined reference to `VL53L1X_ClearInterrupt'
VL53L1X_calibration.c:(.text+0x26f): undefined reference to `VL53L1X_GetSpadNb'
VL53L1X_calibration.c:(.text+0x2c3): undefined reference to `VL53L1X_StopRanging'
VL53L1X_calibration.c:(.text+0x376): undefined reference to `VL53L1_WrWord'
main.o: In function `VL53L1X_CalibrateOffset':
VL53L1X_calibration.c:(.text+0x44): undefined reference to `VL53L1_WrWord'
VL53L1X_calibration.c:(.text+0x5c): undefined reference to `VL53L1_WrWord'
VL53L1X_calibration.c:(.text+0x74): undefined reference to `VL53L1_WrWord'
VL53L1X_calibration.c:(.text+0x82): undefined reference to `VL53L1X_StartRanging'
VL53L1X_calibration.c:(.text+0xa3): undefined reference to `VL53L1X_CheckForDataReady'
VL53L1X_calibration.c:(.text+0xc0): undefined reference to `VL53L1X_GetDistance'
VL53L1X_calibration.c:(.text+0xce): undefined reference to `VL53L1X_ClearInterrupt'
VL53L1X_calibration.c:(.text+0xfa): undefined reference to `VL53L1X_StopRanging'
VL53L1X_calibration.c:(.text+0x14f): undefined reference to `VL53L1_WrWord'
main.o: In function `VL53L1X_CalibrateXtalk':
VL53L1X_calibration.c:(.text+0x1cf): undefined reference to `VL53L1_WrWord'
VL53L1X_calibration.c:(.text+0x1dd): undefined reference to `VL53L1X_StartRanging'
VL53L1X_calibration.c:(.text+0x201): undefined reference to `VL53L1X_CheckForDataReady'
VL53L1X_calibration.c:(.text+0x21e): undefined reference to `VL53L1X_GetSignalRate'
VL53L1X_calibration.c:(.text+0x233): undefined reference to `VL53L1X_GetDistance'
VL53L1X_calibration.c:(.text+0x241): undefined reference to `VL53L1X_ClearInterrupt'
VL53L1X_calibration.c:(.text+0x26f): undefined reference to `VL53L1X_GetSpadNb'
VL53L1X_calibration.c:(.text+0x2c3): undefined reference to `VL53L1X_StopRanging'
VL53L1X_calibration.c:(.text+0x376): undefined reference to `VL53L1_WrWord'
collect2: error: ld returned 1 exit status
makefile:33: recipe for target 'driver' failed
make: *** [driver] Error 1
如果您查看这些行：
Building API/core/VL53L1X_calibration.o
gcc -I. -IAPI/core -IAPI/platform -MMD -MP -Wall -c API/core/VL53L1X_calibration.c -o API/core/VL53L1X_calibration.o
Building API/core/VL53L1X_api.o
gcc -I. -IAPI/core -IAPI/platform -MMD -MP -Wall -c API/core/VL53L1X_calibration.c -o API/core/VL53L1X_api.o
Building API/platform/vl53l1_platform.o
gcc -I. -IAPI/core -IAPI/platform -MMD -MP -Wall -c API/core/VL53L1X_calibration.c -o API/platform/vl53l1_platform.o
Building main.o
gcc -I. -IAPI/core -IAPI/platform -MMD -MP -Wall -c API/core/VL53L1X_calibration.c -o main.o
您将看到您正在使用相同的源文件来创建每个对象文件。因此，该函数中定义的任何内容都将被多次定义，而没有定义的内容将被未定义。
这是因为您如何定义对象文件的目标：
$(OBJ): $(SRC) $(HDR)
应该是：
%.o: %.c $(HDR)