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From: dewar@cs.nyu.edu (Robert Dewar)
Subject: Re: Assertions (was: Re: next "big" language?? (disagree))
Date: 1996/06/24
Message-ID: <dewar.835633172@schonberg>#1/1
X-Deja-AN: 161940518
references: <JSA.96Jun18142249@organon.com> <dewar.835121649@schonberg>
 <dewar.835306677@schonberg> <4ql1fv$5ss@goanna.cs.rmit.EDU.AU>
 <DtI7n4.Brz@world.std.com>
organization: Courant Institute of Mathematical Sciences
newsgroups: comp.lang.ada
Date: 1996-06-24T00:00:00+00:00
List-Id: <comp.lang.ada>


Bob Duff said

"
    pragma Suppress(Assertion_Check);
    pragma Assert(...);

for these two cases.  Note that in *both* of these cases, the compiler
can optimize the following code based on the asserted "fact".  These
pragmas are really no different from constraint checks, which may or may
not be suppressed, and which can, of course, affect the behavior of the
program.
"

Not quite, remember that failing an assertion raises Assert_Error, it is
not erroneous, so the compiler cannot assume (not P) at the point where
the assert appears, it can only assume (not P) after the asssertion
which is a VERY much weaker condition.