Re: [ros-dev] Exceptional exception handling

[Timo Kreuzer]

I have looked into this again in a little more detail.
What I think is happening is the following:

in delphi an exception is raised.

Delphi.Sytstem._RaiseExcept
    RaiseException
        RtlRaiseException
            RtlDispatchException
                RtlpExecuteHandlerForExecption
                    Delphi.System._ExceptionHandler
                        UnhandledExceptionFilter

EXCEPTION_DISPOSITION
 __cdecl Delphi.System.ExceptionHandler(
     struct _EXCEPTION_RECORD *ExceptionRecord,
     void * EstablisherFrame,
     struct _CONTEXT *ContextRecord,
     void * DispatcherContext
     );

Source code can be found here (search for _RaiseExcept, _ExceptionHandler):
http://www.getunderstand.com/documents/sample_reports/udelphi_example_repor…

what you can see in the code for _ExceptionHandler is
10680         LEA     EAX,[ESP+4]
10681         PUSH    EAX
10682         CALL    UnhandledExceptionFilter

This is an unmodified esp, so esp points to the return address and esp+4
points to the function parameters
so it's effectively doing something like

|EXCEPTION_POINTER ExceptionPointers;
||||ExceptionPointers||||.||ExceptionRecord| = ExceptionRecord;|
ExceptionPointers||||.||||ContextRecord| = EstablisherFrame;
UnhandledExceptionFilter(&|ExceptionPointers|);

It is done that way in multiple locations (line 9641, 9666 (push / esp+8), 10028, 10064,
...)
so It's obviously done intentionally.