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From:	Hans-Bernhard Broeker <broeker AT physik DOT rwth-aachen DOT de>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Alignment problem
Date:	8 Feb 2002 12:49:58 GMT
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Eli Zaretskii <eliz AT is DOT elta DOT co DOT il> wrote:

> The language standard (at least C99) does require malloc to return a
> pointer that is suitably aligned for the types of object for which the
> pointer could be used.  

Even byte alignment only would be "suitably aligned" in x86 world.
Sure, there's a performance hit if you have unaligned objects, but
that's not what the standard referst to when it says "suitable",
AFAIK.  That just means the CPU must accept the pointer as a pointer
to arbitrary types without crashing the program.  

> In practice, for x86 CPUs, this means that any object that is 8
> bytes or larger needs to be aligned on 8-byte boundary.

It doesn't exactly "need" to be.  It certainly should, if possible.
But that's a quality of implementation issue, not one of fulfilling
Standard requirements.

-- 
Hans-Bernhard Broeker (broeker AT physik DOT rwth-aachen DOT de)
Even if all the snow were burnt, ashes would remain.

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