[eigen] ftbfs basicstuff_4 test with visual studio 10

[Michel Zou <Xantares09@xxxxxxxxxxx>]

hi,

just letting you know, basicstuff_4 test cannot be built with vs10 anymore with latest eigen version 3.3.1:

Building CXX object test/CMakeFiles/basicstuff_4.dir/basicstuff.cpp.obj

basicstuff.cpp

c:\miniconda3-x64\conda-bld\work\eigen-eigen-f562a193118d\eigen\src/Core/CommaInitializer.h(103) : warning C4290: C++ exception specification ignored except to indicate a function is not __declspec(nothrow)

c:\miniconda3-x64\conda-bld\work\eigen-eigen-f562a193118d\eigen\src/Core/CommaInitializer.h(128) : see reference to class template instantiation 'Eigen::CommaInitializer<Derived>' being compiled

c:\miniconda3-x64\conda-bld\work\eigen-eigen-f562a193118d\test\main.h(381) : error C2668: 'sqrt' : ambiguous call to overloaded function

c:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\INCLUDE\math.h(589): could be 'long double sqrt(long double)'

c:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\INCLUDE\math.h(541): or 'float sqrt(float)'

c:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\INCLUDE\math.h(127): or 'double sqrt(double)'

while trying to match the argument list '(RealScalar)'