[PATCH] Eliminate third argument from _JMPBUF_UNWINDS

[Andreas Schwab]

Roland McGrath <roland@hack.frob.com> writes:

>> Roland McGrath <roland@hack.frob.com> writes:
>> 
>> > This all but ensures that when a machine adds PTR_MANGLE/PTR_DEMANGLE
>> > support, or changes how it does the mangling, that the corresponding
>> > update in jmpbuf-unwind.h will be forgotten.
>> 
>> That will not happen.
>
> Your assertion alone does not reassure me.  
> What guarantees this will not happen?

Because I obviously didn't change anything here.  If you think there is
something wrong then it's not my fault.

> In the current scheme the caller does not have knowledge of jmp_buf
> internals.  It is required to supply a function that performs PTR_DEMANGLE.
> That's all it knows.  _JMPBUF_UNWINDS has the knowledge of how that
> function is useful in interpreting a jmp_buf.

It is still a layering violation and bad code duplication.  The callers
are not suposed to know about the mangling.  Moreover, the macros is
useless without demangling.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
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