C++ lib build Windows VS2022: Build fails with platform toolset v143 – works with platform toolset v142

I am having the following issue with building a simple library (FLANN) from source on windows.

1. I get the code and use CMAKE to generate the VSSolution. Note
   that I am disabling python, c and matlab bindings. All good so far.
2. I am using Visual Studio 2022 – Platform toolset v143 C++ ISO 14.

I get the following compile error on the heap.h file:

heap.h(108,50): error C2143: syntax error: missing ',' before '<'

This is the faulting snippet:

struct CompareT : public std::binary_function<T,T,bool> 
{ 
bool operator()(const T& t_1, const T& t_2) const { return t_2 < t_1; } 
};

NOW, if I change the platform toolset to v142, it works.

I strongly think this is a bug. I am not the best C++ programmer out there and I do not know the nuances on why the same code fails when using v143 instead of v142.

What can I do to fix the code in heap.h so that it will build in v143?

Thank you!

>Solution :

std::binary_function was removed in C++17. The latest version of the library you are building seems to have fixed this problem. So you could upgrade to the latest version (that would be my recommendation) or you could apply the change made to your version of the source.