我有一个带有源文件的项目（每个函数也有一个.h）：
- test_functions.c
- 函数1.c
- 函数2.c
- 函数3.c
- func4.c
- func5.c
我得到一个未定义的引用，test_functions.c用于func3.c.
到目前为止的步骤：
make VERBOSE=1显示 func3.c 的构建和 func3.co 的链接nm func3.c.o显示符号已定义readelf -s func3.c.o还定义了显示符号make VERBOSE=1显示正在使用 gcc，而不是名称修改问题
这就是它变得有趣的地方，我疯狂并删除了func3.c重新编译，现在我得到了未定义的引用func3（显然），现在还有一个未定义的引用func2!! 然而我之前已经用那个函数编译过！
如果我添加func3.c回源代码，请注释掉对func3()我可以调用的函数调用func2()......我完全不知所措。
要求编译：
Scanning dependencies of target test_opencl_functions
make[2]: Leaving directory `/home/constantin/workspace/durp/tests/release_arm'
make -f CMakeFiles/test_opencl_functions.dir/build.make CMakeFiles/test_opencl_functions.dir/build
make[2]: Entering directory `/home/constantin/workspace/durp/tests/release_arm'
/usr/bin/cmake -E cmake_progress_report /home/constantin/workspace/durp/tests/release_arm/CMakeFiles 14
[ 53%] Building C object CMakeFiles/test_opencl_functions.dir/src/opencl/opencl_functions/openclpyramid.c.o
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/usr/bin/cmake -E cmake_progress_report /home/constantin/workspace/durp/tests/release_arm/CMakeFiles 19
[ 73%] Building C object CMakeFiles/test_opencl_functions.dir/src/opencl/opencl_functions/openclrgbtogray.c.o
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[ 76%] Building C object CMakeFiles/test_opencl_functions.dir/src/opencl/test_functions.c.o
/usr/bin/arm-linux-gnueabi-gcc-4.5 -mthumb -fdata-sections -Wa,--noexecstack -fsigned-char -Wno-psabi -mfpu=vfpv3-d16 -mthumb -fdata-sections -Wa,--noexecstack -fsigned-char -Wno-psabi -mfpu=vfpv3-d16 -I/home/constantin/workspace/durp/tests/../PanasonicCameraLib -I/home/constantin/workspace/durp/tests/../linux_arm_tool/include -o CMakeFiles/test_opencl_functions.dir/src/opencl/test_functions.c.o -c /home/constantin/workspace/durp/tests/src/opencl/test_functions.c
Linking C executable test_opencl_functions
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CMakeFiles/test_opencl_functions.dir/src/opencl/test_functions.c.o: In function `TestPyramid':
test_functions.c:(.text+0x89c): undefined reference to `opencl_pyramid'