From: kagel AT quasar DOT bloomberg DOT com
Date: Tue, 18 Feb 1997 16:46:06 -0500
Message-Id: <9702182146.AA02177@quasar.bloomberg.com >
To: beppu AT rigel DOT oac DOT uci DOT edu
Cc: djgpp AT delorie DOT com
In-Reply-To: <5dvv1h$ar9@news.service.uci.edu> (beppu@rigel.oac.uci.edu)
Subject: Re: [Q] malloc() and assumptions about alignment
Reply-To: kagel AT dg1 DOT bloomberg DOT com

   Errors-To: postmaster AT ns1
   From: beppu AT rigel DOT oac DOT uci DOT edu (John Beppu)
   Newsgroups: comp.os.msdos.djgpp
   Date: 13 Feb 1997 20:54:09 GMT
   Organization: University of California, Irvine
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     question 1	Is it safe to assume that memory allocated with
		   malloc() will be aligned on at least a 4 byte
		   boundary.  (using djgpp)

     question 2	Is it safe to assume the above will be true of
		   ports of gcc to other platforms?

     question 3	...and what about other non-gcc compilers?



     [information,opinions] are appreciated.



It is safe to assume that any compliant "C" compiler will align malloc()
memory blocks to the most restrictive requirements of the native, or 
target, processor.  On Intel x86 in real mode this is 2byte alignment, in
intel x86 32 bit Protected mode this is 4byte alignment.  For Motorola 
88xx0 , for example, the alignment is 8byte alignment.

-- 
Art S. Kagel, kagel AT quasar DOT bloomberg DOT com

A proverb is no proverb to you 'till life has illustrated it.  -- John Keats