[Bug 25561] Setting watches (hw breakpoints) in debuggers can generate unhandled floating point stack check exceptions

http://bugs.winehq.org/show_bug.cgi?id=25561

Anastasius Focht  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
                 CC|                            |[e-mail]
          Component|winedbg                     |ntdll
            Summary|Setting watches in winedbg  |Setting watches (hw
                   |can generate unhandled      |breakpoints) in debuggers
                   |floating point stack check  |can generate unhandled
                   |exceptions                  |floating point stack check
                   |                            |exceptions
     Ever Confirmed|0                           |1

--- Comment #5 from Anastasius Focht  2011-05-23 05:51:17 CDT ---
Hello,

--- quote ---
Apparently, when a debug register is used by a watchpoint,
raise_trap_exception() inadvertently removes the FPU state from the context,
and so when wineserver subsequently serves a get_thread_context request from
the debugger, it does not have the FPU state to pass to the debugger (i.e. in
the server's copy_context(), the FPU state is in flags but not in from->flags).
--- quote ---

good catch.
I've occasionally seen this behaviour with other debuggers as well (like
ollydbg) when using hw breakpoints in apps that make use of fp (VB apps do).

Regards