On Thu, 10 Jun 2021 at 13:28, Vladimir Grigoriev via Std-Discussion <std-discussion@lists.isocpp.org> wrote:
Also is it this rule valid for designated initializations?
 
For example if we have
 
struct A
{
    int x, z;
};
struct B
{
    int x, y, z;
};
void g( const A & )
{
    std::cout << "void g( const A & )\n";
}
void g( const B & )
{
    std::cout << "void g( const B & )\n";
}
 
then is this call
 
    g( { .x = 1, .z = 2 } );
 
ambiguous or the function with the parameter const A & will be called?

A and B are not array types, so [over.ics.rank]/3.1.2 does not apply.

Indeed, all the compilers agree that the call is ambiguous.