[CMake] library link order

[Andreas Naumann]

Hello,

I have cmake project, which tries to link against external libraries using

target_link_libraries(myExec ${EXTERNAL_LIBS})

When compiling and linking the executable using make, I can see that 
some libraries are doubled in the link line, but not all.
At the current stage, I think, that this leads to the linker errors with 
missing simbols of libraries, which are not doubled on the link command.

My question are now
     a) why does cmake double some libraries?
     b) which are append twice?


I am using cmake version 2.8.11.