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Groups > comp.lang.c.moderated > #378
| From | James Kuyper <jameskuyper@verizon.net> |
|---|---|
| Newsgroups | comp.lang.c.moderated |
| Subject | Re: which one is faster? |
| Date | 2012-04-23 08:31 -0500 |
| Organization | A noiseless patient Spider |
| Message-ID | <clcm-20120423-0001@plethora.net> (permalink) |
| References | <clcm-20120404-0002@plethora.net> |
On 04/04/2012 07:05 PM, echo ma wrote:
> on a 32bit system.
>
> #pragma pack(4)
> struct TestStruct
> {
> unsigned short a;
> unsigned short b;
> unsigned int c;
> };
> #pragma pack()
> struct TestStruct t;
> t.a = 0; //step 1
> t.b = 1; //step 2
> t.c = 2; //step 3
>
> Questing is : Are these 3 steps having the same perfomance time?
On some systems, #pragma pack() won't even be recognized as a supported
#pragma. It's not defined by the standard, and it might have different
effects on different systems.
Even on systems where #pragma pack() is recognized, and has similar
effects, there is no general answer to that question, just different
answers for different systems, and those answers will differ even on the
same system, depending upon the context. Tell us which 32-bit system
you're using, and if anyone has a similar system, they'll be able to
perform tests to determine which one is faster.
--
James Kuyper
--
comp.lang.c.moderated - moderation address: clcm@plethora.net -- you must
have an appropriate newsgroups line in your header for your mail to be seen,
or the newsgroup name in square brackets in the subject line. Sorry.
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which one is faster? echo ma <fatmck@gmail.com> - 2012-04-04 18:05 -0500
Re: which one is faster? James Kuyper <jameskuyper@verizon.net> - 2012-04-23 08:31 -0500
Re: which one is faster? "Joel C. Salomon" <joelcsalomon@gmail.com> - 2012-04-23 08:33 -0500
Re: which one is faster? David Brown <david@westcontrol.removethisbit.com> - 2012-04-23 08:33 -0500
Re: which one is faster? Thomas Richter <thor@math.tu-berlin.de> - 2012-04-23 08:31 -0500
Re: which one is faster? Keith Thompson <kst-u@mib.org> - 2012-04-30 21:57 -0500
Re: which one is faster? Barry Schwarz <schwarzb@dqel.com> - 2012-04-23 08:32 -0500
Re: which one is faster? Keith Thompson <kst-u@mib.org> - 2012-04-23 08:32 -0500
Re: which one is faster? George Neuner <gneuner2@comcast.net> - 2012-04-30 21:58 -0500
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