Re: Large writable variables

On Tue, Oct 16, 2018 at 12:26 PM Andres Freund <andres(at)anarazel(dot)de> wrote:
> /*
> * Macro that allows to cast constness away from a variable, but doesn't
> * allow changing the underlying type. Enforcement of the latter
> * currently only works for gcc like compilers.
> *
> * Please note IT IS NOT SAFE to cast constness away if the variable will ever
> * be modified (it would be undefined behaviour). Doing so anyway can cause
> * compiler misoptimizations or runtime crashes (modifying readonly memory).
> * It is only safe to use when the the variabble will not be modified, but API
> * design or language restrictions prevent you from declaring that
> * (e.g. because a function returns both const and non-const variables).
> */

"variabble" is a little too rich in "b"s.

In terms of a function that returns both const and non-const
variables, it seems a bit sketchy that the caller would know what the
function is doing in particular cases and make decisions based on it,
but maybe that's just how life is.

--
Robert Haas
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