Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.c > #148206

Re: sizeof object got by dereferencing uniniitalized pointer

Path csiph.com!eternal-september.org!feeder.eternal-september.org!reader01.eternal-september.org!.POSTED!not-for-mail
From Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups comp.lang.c
Subject Re: sizeof object got by dereferencing uniniitalized pointer
Date Thu, 28 Nov 2019 16:37:46 -0800
Organization A noiseless patient Spider
Lines 19
Message-ID <86eexr8qlh.fsf@linuxsc.com> (permalink)
References <21e377ab-2a49-4f7e-bc18-72f1cee63204@googlegroups.com> <9d5ee6d4-607b-405f-83d9-afbe2b073cac@googlegroups.com> <76a74489-4a1f-4561-a01b-b2962a10bae4@googlegroups.com> <qromtr$3o3$1@dont-email.me> <2119c5dc-fc01-4a74-93f4-8027c7cc210e@googlegroups.com> <c97a16bb-4384-5e83-2c2f-1099b62be653@hrosenau.de> <43093894-ed52-47de-85f4-eadd92a1499e@googlegroups.com> <877e3j52do.fsf@bsb.me.uk>
Mime-Version 1.0
Content-Type text/plain; charset=us-ascii
Injection-Info reader02.eternal-september.org; posting-host="81b92e3fa8397acac1ab5cf195ff75cd"; logging-data="26130"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX18zoO3VIWZvfXqBglXaXrogWkYjpZOClno="
User-Agent Gnus/5.11 (Gnus v5.11) Emacs/22.4 (gnu/linux)
Cancel-Lock sha1:Ij6ycQqdB/xrdihNekvPvvZIoaw= sha1:Mf5w3Hc5VJzb4t+y6SzWohu3KUI=
Xref csiph.com comp.lang.c:148206

Show key headers only | View raw

Ben Bacarisse <ben.usenet@bsb.me.uk> writes:

> Thiago Adams <thiago.adams@gmail.com> writes:
> <cut>
>
>> Only when applied to variably types, sizeof is in runtime.
>>
>>   int n = 10;
>>
>>   int(*buf)[n] = malloc(sizeof(int) * n);
>
> Why would you not write
>
>    int (*buf)[n] = malloc(sizof *buf);
>
> ?

Perhaps because, technically speaking, the right-hand side here
has undefined behavior?

Back to comp.lang.c | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

sizeof object got by dereferencing uniniitalized pointer "V.Subramanian, India" <subramanian100in@yahoo.com> - 2019-11-28 05:20 -0800
  Re: sizeof object got by dereferencing uniniitalized pointer Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2019-11-28 05:37 -0800
    Re: sizeof object got by dereferencing uniniitalized pointer mark.bluemel@gmail.com - 2019-11-28 05:59 -0800
      Re: sizeof object got by dereferencing uniniitalized pointer David Brown <david.brown@hesbynett.no> - 2019-11-28 15:51 +0100
        Re: sizeof object got by dereferencing uniniitalized pointer Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2019-11-28 07:27 -0800
          Re: sizeof object got by dereferencing uniniitalized pointer Herbert Rosenau <nospam@hrosenau.de> - 2019-11-28 17:28 +0100
            Re: sizeof object got by dereferencing uniniitalized pointer Thiago Adams <thiago.adams@gmail.com> - 2019-11-28 08:51 -0800
              Re: sizeof object got by dereferencing uniniitalized pointer Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-11-28 17:36 +0000
                Re: sizeof object got by dereferencing uniniitalized pointer Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-11-28 16:37 -0800
                Re: sizeof object got by dereferencing uniniitalized pointer Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-11-29 01:27 +0000
                Re: sizeof object got by dereferencing uniniitalized pointer Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-11-28 17:47 -0800
                Re: sizeof object got by dereferencing uniniitalized pointer Richard Damon <Richard@Damon-Family.org> - 2019-11-28 21:16 -0500
                Re: sizeof object got by dereferencing uniniitalized pointer Keith Thompson <kst-u@mib.org> - 2019-11-29 00:38 -0800
                Re: sizeof object got by dereferencing uniniitalized pointer Richard Damon <Richard@Damon-Family.org> - 2019-11-29 09:03 -0500
                Re: sizeof object got by dereferencing uniniitalized pointer Keith Thompson <kst-u@mib.org> - 2019-11-29 13:15 -0800
                Re: sizeof object got by dereferencing uniniitalized pointer Keith Thompson <kst-u@mib.org> - 2019-11-29 13:38 -0800
                Re: sizeof object got by dereferencing uniniitalized pointer Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-11-29 07:09 -0800
                Re: sizeof object got by dereferencing uniniitalized pointer Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-11-29 06:10 -0800
                Re: sizeof object got by dereferencing uniniitalized pointer Richard Damon <Richard@Damon-Family.org> - 2019-11-29 11:12 -0500
                Re: sizeof object got by dereferencing uniniitalized pointer Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-12-01 09:32 -0800
                Re: sizeof object got by dereferencing uniniitalized pointer Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-11-29 07:39 -0800
                Re: sizeof object got by dereferencing uniniitalized pointer Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-11-29 22:00 +0000
                Re: sizeof object got by dereferencing uniniitalized pointer Richard Damon <Richard@Damon-Family.org> - 2019-11-29 22:40 -0500
                Re: sizeof object got by dereferencing uniniitalized pointer Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-11-30 11:19 +0000
                Re: sizeof object got by dereferencing uniniitalized pointer Richard Damon <Richard@Damon-Family.org> - 2019-11-30 09:01 -0500
                Re: sizeof object got by dereferencing uniniitalized pointer Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-12-01 10:28 -0800
              Re: sizeof object got by dereferencing uniniitalized pointer Richard Damon <Richard@Damon-Family.org> - 2019-11-28 12:49 -0500
                Re: sizeof object got by dereferencing uniniitalized pointer Thiago Adams <thiago.adams@gmail.com> - 2019-11-28 11:26 -0800
                Re: sizeof object got by dereferencing uniniitalized pointer Richard Damon <Richard@Damon-Family.org> - 2019-11-28 17:19 -0500
                Re: sizeof object got by dereferencing uniniitalized pointer Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-11-28 17:26 -0800
                Re: sizeof object got by dereferencing uniniitalized pointer Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-11-28 22:34 +0000
          Re: sizeof object got by dereferencing uniniitalized pointer Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-11-28 17:34 +0000
      You gotta wonder why people say things like this! (Was: sizeof object got by dereferencing uniniitalized pointer) gazelle@shell.xmission.com (Kenny McCormack) - 2019-11-28 17:19 +0000
    Re: sizeof object got by dereferencing uniniitalized pointer Keith Thompson <kst-u@mib.org> - 2019-11-28 14:55 -0800
      Re: sizeof object got by dereferencing uniniitalized pointer "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-11-30 15:28 -0800

csiph-web