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From: Ed Avis <ed@membled.com>
Newsgroups: comp.lang.ada,comp.lang.c++.moderated
Subject: Re: C bug of the day
Date: 15 Jun 2003 17:59:54 -0400
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Date: 2003-06-15T17:59:54-04:00
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LLeweLLyn <llewelly.at@xmission.dot.com> writes:

>>>>In Ada, GC is automatic for stack variables,
>>
>>>In C++ GC is automatic for stack variables as well

>>     int* f()
>>     {
>>         int x = 5;
>>         return &x;
>>     }

>Ada has no more (and no less) garbage collection here than C++
>does. In both cases, stack variables are deallocated at the end of
>the function or subprogram. What Ada does have is checked accesibilty
>rules that prevent returning a pointer to a local object.

I suppose this is a conservative analysis associating a scope level
with each variable (as part of its type) and forbidding assignment or
initialization (or whatever the equivalent Ada terms are) of a value
to a variable not in the same scope or in a deeper scope.

Does this check ever get in the way of expressing reasonable programs?
Could not C and C++ have the same check?

-- 
Ed Avis <ed@membled.com>

      [ See http://www.gotw.ca/resources/clcm.htm for info about ]
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