The library may be implemented in C++, but libsvm.h is a C header file. We've been using this patch to build clisp successfully for Fedora with a C compiler for the last 4 years since I posted the patch.
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Patch to fix libsvm module compilation failure
libsvm is a C++ library, I am not sure you can compile with C
The library may be implemented in C++, but libsvm.h is a C header file. We've been using this patch to build clisp successfully for Fedora with a C compiler for the last 4 years since I posted the patch.