🚀 go-pugleaf

To Moderator: This may be a duplicate, my newsreader software was having
trouble sending this, so I'm mailing it as well.

In 3.7.3.2.4 the January working paper says:

4 A deallocation function can free the storage referenced by the pointer
  given  as  its  argument and renders the pointer invalid.  The storage
  can be made available for further allocation.  An invalid pointer con-
  tains an unusable value:  it cannot even be used in an expression.

This sounds as though, in the following:

char *pc = new char[128];
delete pc;
pc = 0;

it makes the final assignment (an expression) invalid.

Am I misunderstanding something, or is it illegal to zero out pointers
after they've been deallocated? I'm assuming that the intent was to
disallow dereferencing of pointers that have been handed to
delete. The wording seems to disallow the above as well.

In fact, it sounds like it also rules out things like 'if(pc == 0)
...' after the above fragment.

Joe


[ comp.std.c++ is moderated.  To submit articles: try just posting with      ]
[ your news-reader.  If that fails, use mailto:std-c++@ncar.ucar.edu         ]
[ FAQ:      http://reality.sgi.com/employees/austern_mti/std-c++/faq.html    ]
[ Policy:   http://reality.sgi.com/employees/austern_mti/std-c++/policy.html ]
[ Comments? mailto:std-c++-request@ncar.ucar.edu                             ]