'goto" gone from computer languages or is it! - test-drb@ccmp.vtda.org

14 May 2005

...
 Sorry to belabor the point, but...

This is the part that I can't find in my C documentation.  I get that there
are multiple assignments before the sequence point, whose order is
"unspecified".  But can't find anything that says the result should be
"undefined", so I assume it should be one of the values (but which one would
still be "unspecified"). 
If it were just a matter of assignments, I might agree with you, however in
this particular case, the code contains three read-modify-write operations on
the same Lvalue all of which occur within the context of side effects within
a single sequence interval. IIRC the behavior in this instance is undefined.

...
 Then again, I am working from the lexical guide, rather
than the standards
documents themselves.  (Can you cite chapter and verse?) 
Sorry, I'm operating from memory - haven't got a clue where my copy is at the
moment (haven't had to make major changes to my compiler in quite a long time).
Here is a reference to a C faq page which cites an example exactly like the
code in this discussion, with references to K&R, ANSI and ISO documents:

   http://www.eskimo.com/~scs/C-faq/q3.2.html

Regards,
Dave
-- 
dave04a (at)    Dave Dunfield
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