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From: awdorrin <awdorrin@gmail.com>
Newsgroups: comp.lang.ada
Subject: GNAT 4.4.5 order of conditional processing?
Date: Tue, 15 Nov 2011 12:30:07 -0800 (PST)
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Date: 2011-11-15T12:30:07-08:00
List-Id: <comp.lang.ada>

Given an IF statement such as the following:

if X = Y and not A and B

How does GNAT handle the processing of the conditional statements?
Will "X = Y" be processed first, and if false, will the rest be
skipped?

Reason I'm asking is I'm porting code, and it appears as if all of the
statements are being evaluated, even though the "X = Y" part is
already false.

I'm not sure if there is some optimization going on and if there is,
is there a compiler flag to disable it.

Guessing the best thing to do would be to rewrite the code to
something clearer like:

if X = Y then
  if not A then
   if B then ...

But I was curious since this is something that is probably a hundred
places through out this collection of source code.

Thanks
-Al