Date: Thu, 4 Mar 1999 21:53:16 +0100 (MET)
From: Gisle Vanem <giva AT bryggen DOT bgnett DOT no>
To: DJGPP mailing list <djgpp AT delorie DOT com>
Subject: Re: C++ exceptions and stack messing
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Reply-To: djgpp AT delorie DOT com

On Thu, 4 Mar 1999, Wojciech Piechowski wrote:

> I'm writing a program that uses some privilege levels using call gates.
> Calling the gate changes the privilege and switches to another stack
> specific to the new privilege. The old stack comes back when the
> privileged routine does 'RET'. I wonder if the privileged function can
> throw exceptions which will be caught by the non-privileged caller?

The protected mode architecture prohibits a transfer to a lower
PL when interrupts/exceptions occur. So, the solution must include
exception handlers at the privileged level (RPL 0) also.

Gisle V.