[lug] new operator in C++

Tkil tkil at scrye.com
Sat Apr 27 17:40:37 MDT 2002

>>>>> "DS" == D Stimits <stimits at idcomm.com> writes:

i think you misunderstood my surprise.

DS> delete was called after each new; thus the same memory slot was
DS> likely to be reused each time. 

right.  but it wasn't, and that's what surprised me.  if it *had* been
re-used, i would have expected to see 1 2 3 4 5 ... and so on.  but
having just 1, then that constant number -- very strange!

DS> Had you done all the new operators in a row on separate variables,
DS> your results would not have been the same in all likelihood. Or if
DS> you had done other memory operations possibly the slot being used
DS> would have been different.

weird, i am getting the same address each time.  something is
overwriting it with a consistent value each time through the loop.
actually, even in the first block (that's not a loop).  

i wonder what's doing it?

and it does seem to do something more than just "put it on a free
list", which is what i thought; if i try to do "*pi = 0" after the
delete, i get a SEGV (even though pi itself has the same value as
before the delete.)

oh well.  confused, and too hungry to step through libstdc++ and glibc
to figure out what's going on.


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