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The C, C++ and Fortran compilers are chosen by CMake. This can be overwritten by setting the environment variables CC, CXX and F77, before the call to cmake, to set the preferred compiler. Further the variable CMAKE_CXX_FLAGS can be used to set compiler flags for optimisation or debugging. For example, using CMAKE_CXX_FLAGS="-O2 -mtune=native" sets options for better optimisation.
Finding support libraries
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