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From: dewar@gnat.com
To: dewar@gnat.com, gcc@gcc.gnu.org, torvalds@transmeta.com
Subject: Re: Big-endian Gcc on Intel IA32
Message-Id: <20011217211252.431D3F28BD@nile.gnat.com>
Date: Mon, 17 Dec 2001 13:14:00 -0000
X-SW-Source: 2001-12/txt/msg00936.txt.bz2

<<<<One thing that might be helpful for portability issues like this, where
the user _is_ willing and able to recompile the application, but maybe
not able to find all subtly users of byte-order dependencies would be to
allow the notion of "byte order attributes" on data structures.
>>


This is a much trickier language feature to design than you would imagine.
We have been struggling with this in Ada for a while.

<<Imagine being able to just tag the data structures with "this data
structure is big-endian", and have the compiler automatically do the
conversion when a value is loaded from such a data structure.
>>

I't snice to imagine, but hard to work out the details.
I am definitely not opposed to this, and indeed support an effort
to try to design such a feature. A good starting point for reading
is Norm Cohen's tutorial on the Bit_Order attribute in Ada (not sure
what the reference is, perhaps someone else can supply it).