matlab2017安装matconvnet-1.0-beta25

然后，运行matlab/vl_compilenn.m，结果总是提示

Error using vl_compilenn>check_compability (line 535)
Unsupported VS C++ compiler, ver >=14.0 required (VS 2015).

Error in vl_compilenn (line 197)
check_compability(arch);

输入： mbuild -setup

MBUILD configured to use 'Microsoft Visual C++ 2015 Professional (C)' for C language compilation.


To choose a different C compiler, select one from the following:
Microsoft Visual C++ 2012 (C)  mex -setup:D:\Matlab17\bin\win64\mexopts\msvc2012.xml C -client MBUILD
Microsoft Visual C++ 2013 Professional (C)  mex -setup:D:\Matlab17\bin\win64\mexopts\msvc2013.xml C -client MBUILD
Microsoft Visual C++ 2015 Professional (C)  mex -setup:C:\Users\wzy\AppData\Roaming\MathWorks\MATLAB\R2017a\MBUILD_C_win64.xml C -client MBUILD


To choose a different language, select one from the following:
 mex -setup C++ -client MBUILD 
 mex -setup FORTRAN -client MBUILD

输入：mex -setup
MEX configured to use 'Microsoft Visual C++ 2015 Professional (C)' for C language compilation.
Warning: The MATLAB C and Fortran API has changed to support MATLAB
 variables with more than 2^32-1 elements. You will be required
 to update your code to utilize the new API.
 You can find more information about this at:
 http://www.mathworks.com/help/matlab/matlab_external/upgrading-mex-files-to-use-64-bit-api.html.


To choose a different C compiler, select one from the following:
Microsoft Visual C++ 2012 (C)  mex -setup:D:\Matlab17\bin\win64\mexopts\msvc2012.xml C
Microsoft Visual C++ 2013 Professional (C)  mex -setup:D:\Matlab17\bin\win64\mexopts\msvc2013.xml C
Microsoft Visual C++ 2015 Professional (C)  mex -setup:C:\Users\wzy\AppData\Roaming\MathWorks\MATLAB\R2017a\mex_C_win64.xml C


To choose a different language, select one from the following:
 mex -setup C++ 
 mex -setup FORTRAN

都改成vs2015了呀，为什么还是有问题？ 

忽然我点了一下  mex -setup C++ ，然后选择vs2015，再运行vl_compilenn 居然就好了