Re: [ros-dev] Re: [Freedce-devel] pthread_clear_exit_np()

[KJKHyperion]

Peter Dolding wrote:
>   Dwarf2 is stack-based and integrated into gcc on a lot
> of platforms.   
>  It uses a slightly different wording frame based.  Basic operation is 
>  the same.  Note if stack-based processor operations were patented 
>  Intel would hold the patent not Borland since they developed the 
>  processor features that let it happen. 
nopes, Borland were the first to do
stack-based exception handling. 
Everyone else used sensible architectures with native unwinding and 
exception handling based on function tables (yes, checked. SEH was 
developed in parallel on Alpha, VAX and x86 - the aforementioned Tru64, 
VMS and OS/2 implementations. And the tradition started back then). And 
besides, wonderful. Microsoft moves away from stack-based and GCC adopts 
it? we're screwed. Also: does it support exception handling in C too, 
now? or only C++? Because we need it in C. GCC's C++ compiler is too 
slow to turn e.g. our whole kernel into C++, and we have the impression 
that it generates gigantic executables. Finally: I see no mention in the 
DWARF specifications of exception handling standards, is this an abusive 
appropriation of the name as an obscure reference to some GCC internals?
>   Its the system of Microsoft/Borland SEH that is
> patented.  Dwarf2 is a 
>  completely independently developed using a different system.  Same 
>  interfaces to processor.  Dwarf2 is not locked to x86 processors.  
>  Dwarf2 has now been extended to Dwarf3 to do support of pure 64 bit 
>  systems. 
stack-based SEH doesn't depend on x86, either, and I find it much
better 
on the whole. In fact, if we can piss on non-x86 compatibility (at least 
temporarily), I'd be very happy to port PSEH (it needs only minimal 
platform-specific code) - I think our system support for exception 
handling could easily support both, even. It's just the way it is in the 
real world
>   Non issue. KJKHyperion not true.  A system exists in
> gcc for frame 
>  based exception handling.  Its used.  Only recently did mingw catch 
>  up. Even djgpp for dos has had it for years.  Mingw is the last gcc to 
>  get it. 
hey, it's not like we didn't pressure them all the time. And to
repeat 
myself, we need this in C. Not C++. Absolutely sure of it. And we'll 
need it to catch faults, such as memory access violations, not just 
program exceptions - in fact, that's what using SEH in the kernel is all 
about