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Date: Fri, 21 Sep 2012 12:21:05 -0700 (PDT)
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Subject: Re: Endianness and Record Specification
From: awdorrin <awdorrin@gmail.com>
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Date: 2012-09-21T12:21:05-07:00
List-Id: <comp.lang.ada>

I think I found the cause of some of my confusion.
The Gnat compiler treats the record specifications differently depending on if the code is compiled as Ada95 or Ada2005...

Under '05 it produces the following output:
mytest.adb:26:22: info: reverse bit order in machine scalar of length 16
mytest.adb:26:22: info: little-endian range for component "Res" is 15 .. 15
mytest.adb:27:22: info: reverse bit order in machine scalar of length 16
mytest.adb:27:22: info: little-endian range for component "Error" is 14 .. 14
mytest.adb:28:22: info: reverse bit order in machine scalar of length 16
mytest.adb:28:22: info: little-endian range for component "WordCnt" is 8 .. 13
mytest.adb:29:22: info: reverse bit order in machine scalar of length 16
mytest.adb:29:22: info: little-endian range for component "BusId" is 7 .. 7
mytest.adb:30:22: info: reverse bit order in machine scalar of length 16
mytest.adb:30:22: info: little-endian range for component "Message" is 0 .. 6

And the big endian specification is reordered. Under Ada95 this does not happen.

Hmm...