Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > comp.lang.c++ > #82617
| From | Keith Thompson <Keith.S.Thompson+u@gmail.com> |
|---|---|
| Newsgroups | comp.lang.c++ |
| Subject | Re: Has "stack overflow" specified behavior? |
| Date | 2021-12-13 15:58 -0800 |
| Organization | None to speak of |
| Message-ID | <8735mw9hvy.fsf@nosuchdomain.example.com> (permalink) |
| References | <f5624610-cbe0-4e27-9f52-f4a900172c89n@googlegroups.com> <877dc89i1n.fsf@nosuchdomain.example.com> |
Keith Thompson <Keith.S.Thompson+u@gmail.com> writes:
> wij <wyniijj@gmail.com> writes:
>> void t() {
>> int a;
>> ++a;
>> t();
>> };
>>
>> int main()
>> {
>> t();
>> }
>>
>> ---
>> Has "stack overflow" specified behavior?
>
> The standard does not specify what happens when a resource limit is
> exceeded. In my opinion that matches the standard's definition of
> "undefined behavior" (behavior that is not defined).
>
> Is the variable `a` intended to track the depth of the recursion? It
> doesn't. A new instance of `a` is created every time t is called. You
> didn't initialize `a`, but if you initialized it to 0 then `++a` would
> simply set it to 1.
>
> If you made `a` static, it would count the depth of the recursion -- and
> you'd have undefined behavior after the value of `a` reaches INT_MAX.
>
> With `a` defined as you did here, there's a distinct instance of `a` for
> each call to t, and each instance has its own distinct address, a value
> of type int*. There can be at most 2**(CHAR_BIT * sizeof (int*))
> distinct int* values. If you never refer to the value or address of `a`,
> an optimizing compiler is likely to eliminate it and change the
> recursive call to a loop, but that doesn't apply in the abstract
> machine. See N1570 5.1.2.3 "Program execution":
>
> The semantic descriptions in this International Standard describe
> the behavior of an abstract machine in which issues of optimization
> are irrelevant.
>
> In the abstract machine, each instance of `a` occupies sizeof (int) bytes
> and has a unique address of type int*. After optimization, `a` might not
> exist.
My apologiess, I didn't notice which newsgroup I was in and gave a C
answer. But the C++ standard also discusses the "abstract machine" in
section 4.6 [intro.execution], with a very similar meaning.
--
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
Working, but not speaking, for Philips
void Void(void) { Void(); } /* The recursive call of the void */
Back to comp.lang.c++ | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
Has "stack overflow" specified behavior? wij <wyniijj@gmail.com> - 2021-12-12 00:42 -0800
Re: Has "stack overflow" specified behavior? Bonita Montero <Bonita.Montero@gmail.com> - 2021-12-12 09:52 +0100
Re: Has "stack overflow" specified behavior? red floyd <no.spam.here@its.invalid> - 2021-12-12 12:59 -0800
Re: Has "stack overflow" specified behavior? Paavo Helde <eesnimi@osa.pri.ee> - 2021-12-13 01:51 +0200
Re: Has "stack overflow" specified behavior? Juha Nieminen <nospam@thanks.invalid> - 2021-12-13 05:48 +0000
Re: Has "stack overflow" specified behavior? Bo Persson <bo@bo-persson.se> - 2021-12-13 10:44 +0100
Re: Has "stack overflow" specified behavior? wij <wyniijj@gmail.com> - 2021-12-13 04:44 -0800
Re: Has "stack overflow" specified behavior? Richard Damon <Richard@Damon-Family.org> - 2021-12-13 07:47 -0500
Re: Has "stack overflow" specified behavior? Bonita Montero <Bonita.Montero@gmail.com> - 2021-12-14 08:32 +0100
Re: Has "stack overflow" specified behavior? Richard Damon <Richard@Damon-Family.org> - 2021-12-14 07:49 -0500
Re: Has "stack overflow" specified behavior? scott@slp53.sl.home (Scott Lurndal) - 2021-12-14 14:23 +0000
Re: Has "stack overflow" specified behavior? "Alf P. Steinbach" <alf.p.steinbach@gmail.com> - 2021-12-14 16:16 +0100
Re: Has "stack overflow" specified behavior? James Kuyper <jameskuyper@alumni.caltech.edu> - 2021-12-13 12:13 -0500
Re: Has "stack overflow" specified behavior? Öö Tiib <ootiib@hot.ee> - 2021-12-13 12:05 -0800
Re: Has "stack overflow" specified behavior? "james...@alumni.caltech.edu" <jameskuyper@alumni.caltech.edu> - 2021-12-13 17:11 -0800
Re: Has "stack overflow" specified behavior? "james...@alumni.caltech.edu" <jameskuyper@alumni.caltech.edu> - 2021-12-13 19:00 -0800
Re: Has "stack overflow" specified behavior? Öö Tiib <ootiib@hot.ee> - 2021-12-13 23:03 -0800
Re: Has "stack overflow" specified behavior? Bonita Montero <Bonita.Montero@gmail.com> - 2021-12-14 08:33 +0100
Re: Has "stack overflow" specified behavior? David Brown <david.brown@hesbynett.no> - 2021-12-14 09:13 +0100
Re: Has "stack overflow" specified behavior? Juha Nieminen <nospam@thanks.invalid> - 2021-12-14 10:09 +0000
Re: Has "stack overflow" specified behavior? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-12-14 16:14 +0000
Re: Has "stack overflow" specified behavior? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-12-14 15:23 -0800
Re: Has "stack overflow" specified behavior? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-12-14 16:10 +0000
Re: Has "stack overflow" specified behavior? Bonita Montero <Bonita.Montero@gmail.com> - 2021-12-14 17:38 +0100
Re: Has "stack overflow" specified behavior? scott@slp53.sl.home (Scott Lurndal) - 2021-12-14 17:09 +0000
Re: Has "stack overflow" specified behavior? Bonita Montero <Bonita.Montero@gmail.com> - 2021-12-14 18:39 +0100
Re: Has "stack overflow" specified behavior? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-12-14 11:01 -0800
Re: Has "stack overflow" specified behavior? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-12-14 10:52 -0800
Re: Has "stack overflow" specified behavior? David Brown <david.brown@hesbynett.no> - 2021-12-14 20:15 +0100
Re: Has "stack overflow" specified behavior? Richard Damon <Richard@Damon-Family.org> - 2021-12-14 07:59 -0500
Re: Has "stack overflow" specified behavior? "Alf P. Steinbach" <alf.p.steinbach@gmail.com> - 2021-12-14 16:19 +0100
Re: Has "stack overflow" specified behavior? James Kuyper <jameskuyper@alumni.caltech.edu> - 2021-12-14 11:33 -0500
Re: Has "stack overflow" specified behavior? Manfred <noname@add.invalid> - 2021-12-13 17:23 +0100
Re: Has "stack overflow" specified behavior? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2021-12-15 23:27 +0000
Re: Has "stack overflow" specified behavior? David Brown <david.brown@hesbynett.no> - 2021-12-16 08:37 +0100
Re: Has "stack overflow" specified behavior? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-12-13 14:16 -0800
Re: Has "stack overflow" specified behavior? wij <wyniijj@gmail.com> - 2021-12-13 15:07 -0800
Re: Has "stack overflow" specified behavior? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-12-16 05:53 -0800
Re: Has "stack overflow" specified behavior? wij <wyniijj@gmail.com> - 2021-12-16 08:34 -0800
Re: Has "stack overflow" specified behavior? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-12-16 12:17 -0800
Re: Has "stack overflow" specified behavior? wij <wyniijj@gmail.com> - 2021-12-16 13:38 -0800
Re: Has "stack overflow" specified behavior? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-12-16 14:15 -0800
Re: Has "stack overflow" specified behavior? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-12-16 20:10 -0800
Re: Has "stack overflow" specified behavior? Öö Tiib <ootiib@hot.ee> - 2021-12-16 14:14 -0800
Re: Has "stack overflow" specified behavior? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-12-16 20:20 -0800
Re: Has "stack overflow" specified behavior? Öö Tiib <ootiib@hot.ee> - 2021-12-17 08:46 -0800
Re: Has "stack overflow" specified behavior? Paavo Helde <eesnimi@osa.pri.ee> - 2021-12-14 10:32 +0200
Re: Has "stack overflow" specified behavior? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-12-16 07:42 -0800
Re: Has "stack overflow" specified behavior? Chris Vine <chris@cvine--nospam--.freeserve.co.uk> - 2021-12-17 01:07 +0000
Re: Has "stack overflow" specified behavior? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-12-17 01:28 +0000
Re: Has "stack overflow" specified behavior? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-12-16 19:54 -0800
Re: Has "stack overflow" specified behavior? Chris Vine <chris@cvine--nospam--.freeserve.co.uk> - 2021-12-17 10:06 +0000
Re: Has "stack overflow" specified behavior? Manfred <noname@add.invalid> - 2021-12-13 17:08 +0100
Re: Has "stack overflow" specified behavior? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-12-13 13:50 -0800
Re: Has "stack overflow" specified behavior? Manfred <noname@add.invalid> - 2021-12-14 16:32 +0100
Re: Has "stack overflow" specified behavior? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-12-13 13:13 -0800
Re: Has "stack overflow" specified behavior? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-12-13 15:55 -0800
Re: Has "stack overflow" specified behavior? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-12-13 15:58 -0800
Re: Has "stack overflow" specified behavior? wij <wyniijj@gmail.com> - 2021-12-14 01:41 -0800
csiph-web