Question

我正在尝试从英特尔MKL库（/opt/intel/mkl/examples/versionqueryc/）编译示例程序。我将源代码（C文件）复制到一个新目录。然后我去尝试用CMake构建这个例子。

在调试过程中，我在尝试使用以下命令时遇到困难（现在与cmake隔离）。

它找不到数学库，但链接中包含-lm。那是怎么回事？

:~/devel/mkl/MKL Test/build$  /usr/bin/gcc -m64 CMakeFiles/mkltest.dir/main.c.o \
>     -o mkltest    -rdynamic -L/home/myuser/src/intel/mkl/lib/intel64 \
>     -lm  -lmkl_intel_lp64 -lmkl_sequential -lmkl_core  -lmkl_cdft_core \
>     -lmkl_scalapack_lp64 \
>     /home/myuser/src/intel/lib/intel64/libiomp5.so \
>     -Wl,-rpath,/home/myuser/src/intel/mkl/lib/intel64:/home/myuser/src/intel/lib/intel64 
/home/myuser/src/intel/mkl/lib/intel64/libmkl_core.so: undefined reference to `logf'
/home/myuser/src/intel/mkl/lib/intel64/libmkl_core.so: undefined reference to `atan2'
/home/myuser/src/intel/mkl/lib/intel64/libmkl_core.so: undefined reference to `sin'
/home/myuser/src/intel/mkl/lib/intel64/libmkl_core.so: undefined reference to `fabs'
/home/myuser/src/intel/mkl/lib/intel64/libmkl_core.so: undefined reference to `exp'
/home/myuser/src/intel/mkl/lib/intel64/libmkl_core.so: undefined reference to `sqrtf'
/home/myuser/src/intel/mkl/lib/intel64/libmkl_core.so: undefined reference to `cos'
/home/myuser/src/intel/mkl/lib/intel64/libmkl_core.so: undefined reference to `sqrt'
/home/myuser/src/intel/mkl/lib/intel64/libmkl_sequential.so: undefined reference to `log'
/home/myuser/src/intel/mkl/lib/intel64/libmkl_core.so: undefined reference to `pow'
/home/myuser/src/intel/mkl/lib/intel64/libmkl_core.so: undefined reference to `log10'
/home/myuser/src/intel/mkl/lib/intel64/libmkl_core.so: undefined reference to `ceil'
/home/myuser/src/intel/mkl/lib/intel64/libmkl_core.so: undefined reference to `expf'
collect2: ld returned 1 exit status

Answer 1

将-lm作为最后一个参数，链接时参数的顺序很重要。

尽管链接到数学库，但未定义对`sqrt`的引用

1 个答案: