I compile my code which use Eigen 3.1.3 with g++ 4.4.7 in Linux. It works well, no errors no warning. But if i compile it with Intel icpc 13.1.1, thare are a lot of warnings like

/usr/local/Eigen/src/SparseCore/SparseMatrix.h(637): warning #2196: routine is both "inline" and "noinline"
EIGEN_DONT_INLINE SparseMatrix& operator=(const SparseMatrixBase<OtherDerived>& other)
^
detected during instantiation of class "Eigen::SparseMatrix<_Scalar, _Options, _Index> [with _Scalar=std::complex<double>, _Options=1, _Index=int]" at line 32 of "bigMatrix.cpp"

It seems that's the problem of "inline", but i don't know how to fix it. Thanks very much.

Those (stupid) warnings have been workaround in the devel branch. Not backported because the branches diverged too much.