tests/misc: check sealed vs. local/global

[nwf]

No description provided.

[rmn30]

I had to add this cast in the same situation recently and it is slightly annoying. Could we have an implicit conversion or is that a bad idea? You can also get rid of if you make oLocal1 const as there is a const version of the permissions method that returns a PermissionSet.

[nwf]

The conversion is already there:

cheriot-rtos/sdk/include/cheri.hh

Lines 625 to 631 in de2db17

	/**
	* Implicitly convert to a permission set.
	*/
	operator PermissionSet() const
	{
	return permission_set_from_pointer(ptr());
	}

However, I believe what's going on is as https://en.cppreference.com/w/cpp/language/template_argument_deduction#Implicit_conversions sayeth:

Type deduction does not consider implicit conversions (other than type adjustments listed above): that's the job for overload resolution, which happens later.

So after type deduction, there's nothing that could define DebugFormatArgumentAdaptor<CHERI::Capability<void>::PermissionsProxy>, and so overload resolution has an empty set of options to consider. AIUI, the static_cast explicitly invokes the implicit conversion, and the const option changes the overload resolution behavior of .permissions(), since the const-qualified option is more specific. Blech.