From mboxrd@z Thu Jan  1 00:00:00 1970
To: 9fans@cse.psu.edu
Date: Wed, 13 Sep 2000 16:44:11 +0000
From: "Douglas A. Gwyn" <DAGwyn@null.net>
Message-ID: <39BFADD3.A6B446C3@null.net>
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References: <20000913143710.99FB9199E2@mail>
Subject: Re: [9fans] no const?
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forsyth@vitanuova.com wrote:
>         volatile: both too little and too much to be useful for the purpose for which it is touted
>         const: confuses the C type system but does not seriously add clarity or protection
>                         (eg, char *strchr(const char *, int))

Those complaints are essentially the same: that the facility
addresses some problems but not all related problems.  This
aspect was well understood when we adopted them for the first
C standard in the 1980s, and the decision was based on getting
some benefit some of the time rather than getting no benefit
all of the time.

Note that the new C standard adds restrict qualification for
pointers, to allow optimizations that otherwise would not be
safe.  "restrict" can be ignored by the compiler, so long as
it doesn't try to make those aggressive optimizations.