What is this compiler error trying to convey?

The test code is as shown below:

#include<vector>
#include<algorithm>
#include<iostream>

using std::vector;
using std::min;
using std::cout;
using std::endl;

int func() 
{
  vector<int>vecI = {1,2,3,4,5};
  auto errVal = 0;
  auto iter = min(vecI.begin(),vecI.end(),errVal);

  cout << *iter << endl;
  
    return 0;   
}

int main() {
    auto exit = (int (*)()) &func;
    
    std::cout << exit() << std::endl;
}

As it should be evident, I am using an erroneous invocation of std::min to generate the following compiler error:

g++ -c -o coliru.o coliru.cpp -ggdb -g3 -pedantic-errors -Wall -Wextra -Wfatal-errors -Wpedantic -std=c++20
In file included from /usr/include/c++/11/vector:60,
                 from coliru.cpp:1:
/usr/include/c++/11/bits/stl_algobase.h: In instantiation of ‘constexpr const _Tp& std::min(const _Tp&, const _Tp&, _Compare) [with _Tp = __gnu_cxx::__normal_iterator<int*, std::vector<int> >; _Compare = int]’:
coliru.cpp:14:18:   required from here
/usr/include/c++/11/bits/stl_algobase.h:281:17: error: ‘__comp’ cannot be used as a function
  281 |       if (__comp(__b, __a))
      |           ~~~~~~^~~~~~~~~~
compilation terminated due to -Wfatal-errors.

I am not sure I can comprehend what the compiler is trying to convey, based on the above error.

Can someone throw some light?

Solution

I am not sure I can comprehend what the compiler is trying to convey, based on the above error.

Can someone throw some light?

Start here.

In instantiation of ‘
    constexpr const _Tp& std::min(const _Tp&, const _Tp&, _Compare)

   [with _Tp = __gnu_cxx::__normal_iterator<int*, std::vector<int> >; _Compare = int]
’

That's the function you are calling. std::min(const _Tp&, const _Tp&, _Compare).

It's a function template, and you are instantiating this template with _Tp as an iterator, and _Compare as an int. Specifically, you passed 0.

error: ‘__comp’ cannot be used as a function

std::min will use __comp as a function and 0 is not usable as a function. The error is telling you this. .