False Positive. Suspicious condition. The result of find() is an iterator, but it is not properly checked.

[Steffen Brauer]

#include <set>
int main()
{
        std::set<int> s;
        if (const auto it = s.find(1); it != s.end()) {}
        return 0;
}

This generates a warning with cppcheck 1.88:

~ $ cppcheck --enable=all cppcheck.cpp
Checking cppcheck.cpp ...
[cppcheck.cpp:5]: (warning) Suspicious condition. The result of find() is an iterator, but it is not properly checked.

[versat]

Thanks for reporting the issue.
It looks like there is already a ticket for such issues: https://trac.cppcheck.net/ticket/9486
I will add your code as another example for the false positive issue.

[versat]

There is also another ticket which is already fixed: https://trac.cppcheck.net/ticket/9630
I closed ticket 9486 as a duplicate one.
That is why I can reproduce the issue with Cppcheck 1.90 but not with the latest development code.
So with the next release (I guess 2.00) the issue is fixed.