From:	Thomas Demmer <demmer AT LSTM DOT Ruhr-UNI-Bochum DOT De>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: sizeof(long double)
Date:	Thu, 06 Mar 1997 12:13:01 +0100
Organization:	Lehrstuhl fuer Stroemungsmechanik
Lines:	41
Message-ID:	<331EA6BD.15FB@LSTM.Ruhr-UNI-Bochum.De>
References:	<Pine DOT SGI DOT 3 DOT 95 DOT 970305141038 DOT 8443A-100000 AT geb DOT gfy DOT ku DOT dk>
NNTP-Posting-Host:	bvb.lstm.ruhr-uni-bochum.de
Mime-Version:	1.0
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Thomas Knudsen wrote:
> 
> Based on the figures in float.h, I have always believed, that a long
> double in djgpp corresponded to an 80 bit IEEE float. However, the
> following code fragment:
> 
> #include <stdio.h>
> #include <stdlib.h>
> int main(void){
>   printf("sizeof(long double)==%d\n", (int) sizeof(long double));
>   return 0;
> }
> 
> prints: sizeof(long double)==12
> 
> is this really true?
> 
> Thomas
You are basically right. On the other hand, variables
are aligned to 4-Byte boundaries in gcc, hence it
take 12 bytes, where the last two bytes are unused.
Other machines may require packing to 8 or 16 byte
boundaries, so things are not always the way they
seem  ;-)


-- 
Ciao
Tom

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* Thomas Demmer                                             *
* Lehrstuhl fuer Stroemungsmechanik                         *
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