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Date: Sat, 18 Mar 2006 15:06:19 +0100
From: Gautier <gautier@fakeaddress.nil>
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Subject: Re: Uninitialized variables (was: Re: private types)
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Date: 2006-03-18T15:06:19+01:00
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Here (trying to to sum up), 3 problems I see with the tactic of
initializing everything:

 - useless initializations (i.e. dummy values rewritten later) take
time and usually _hurt_ performance (think to number crunching with
huge objects, or frequently used functions with local variables)
 - useless initializations introduce meaningless code lines
 - [Dirk] useless initializations prevent detecting bugs that can be
detected without these initializations (they can be detected by
combining the Initialize_Scalars pragma and the validity checks)

My rule is rather to initialize _only_ variables you can give a
meaningful values.
Of course it depends on the context. Maybe there are situations where
you can prefer a program giving wrong results than an unhandled
exception popping at the wrong moment (although I find the method very
shocking!)... In such cases the systematic initialization could be a
way (not nice but pragmatic) to silently disable bug detection.
_______________________________________________________________ 
Gautier         -- http://www.mysunrise.ch/users/gdm/index.htm 
Ada programming -- http://www.mysunrise.ch/users/gdm/gsoft.htm 

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