I've created a sample test code to see if I understand your question correctly:
namespace A
{
void function();
void atan2(double x, double y);
}
namespace B
{
void function();
}
void foo()
{
A::function();
std::atan2(1.0, 2.0);
A::atan2(1.0, 2.0);
}
When I run find references on A::atan2, I don't have std::atan2 in the list. Do you see different result with this code?