[skip appveyor] fplll is a C++ library
export LD_LIBRARY_PATH=$PREFIX/lib:$LD_LIBRARY_PATH
export LDFLAGS="-L$PREFIX/lib $LDFLAGS"
export CFLAGS="-O3 -g -fPIC -I$PREFIX/include $CFLAGS"
+export CXXFLAGS="-O3 -g -fPIC -I$PREFIX/include $CXXFLAGS"
chmod +x configure
