1）mlpack is a C++ machine learning library.
2） PLearn is a C++ library aimed at research and development in the field of statistical machine learning algorithms. Its originality is to allow to easily express, directly in C++ in a straightforward manner, complex non-linear functions to be optimized.
3）Waffles- C++ Machine Learning。
4）Torch7 provides a Matlab-like environment for state-of-the-art machine learning algorithms. It is easy to use and provides a very efficient implementation
5 SHARK is a modular C++ library for the design and optimization of adaptive systems. It provides methods for linear and nonlinear optimization, in particular evolutionary and gradient-based algorithms, kernel-based learning algorithms and neural networks, and various other machine learning techniques. SHARK serves as a toolbox to support real world applications as well as research in different domains of computational intelligence and machine learning. The sources are compatible with the following platforms: Windows, Solaris, MacOS X, and Linux.
6）Dlib-ml is an open source library, targetedat both engineers and research scientists, which aims to provide a similarly rich environment fordeveloping machine learning software in the C++ language.
7) Eblearn is an object-oriented C++ library that implements various machine learning models, including energy-based learning, gradient-based learning for machine composed of multiple heterogeneous modules. In particular, the library provides a complete set of tools for building, training, and running convolutional networks.
8) Machine Learning Open Source Software :Journal of Machine Learning Research: http://jmlr.csail.mit.edu/mloss/.
9) search in google: c++ site:jmlr.csail.mit.edu filetype:pdf , Machine Learning Toolkit
10) SIGMA: Large-Scale and Parallel Machine-Learning Tool Kit