lambda call in default template argument generates mangling error

[sw6ueyz]

this code generates error : cannot yet mangle expression type ImplicitCastExpr

template< bool _ = []( int n, int m ) constexpr { return n < m; }( 1, 2 ) >
void bar()
{
}

int main()
{
	bar();
	return 0;
}

see: https://godbolt.org/z/heZWtU