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To: Eli Zaretskii <eliz@gnu.org>
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Subject: Re: breakpoint for accessing memory location
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Eli Zaretskii wrote:

> The general rule is that watching a constant expression is silly,
> since its value never changes and thus the watchpoint will never
> break.  Thus, it's probably not what the user wanted, and a warning
> would be a Good Thing, IMO.

Right, but of course it is recursively undecidable whether an
expression is constant, so you don't really mean what you say.
What you mean is that warnings could be given in a few cases,
e.g. where the expression is a literal, but going beyond this is a
waste of time, which will not be helpful in practice, no one
is going to watch p-p anyway.