Re: INT_MIN and compiler diagnostic

Beej Jorgensen <beej@xxxxxxx> writes:
[...]
(Interestingly, though, I guess I expected the preprocessor to calculate
the final answer before passing it to the compiler, and it doesn't.

And now, it doesn't even make sense that the preprocessor would do it.
I mean, the compiler has to do that kind of stuff anyway, right?

So why did I have it in the back of my mind that the preprocessor
sometimes did simple math? Some holdover from the olden days of not-so-
optimal compilers?)
[...]

The preprocessor does do simple math within preprocessor directives.
For example:

#if 2 + 2 == 4

is evaluated by the preprocessor.

Arithmetic expressions outside preprocessor directives may be (and in
some cases, must be) evaluated at compilation time, but not during the
preprocessing phases.

--
Keith Thompson (The_Other_Keith) kst-u@xxxxxxx <http://www.ghoti.net/~kst>
San Diego Supercomputer Center <*> <http://users.sdsc.edu/~kst>
"We must do something. This is something. Therefore, we must do this."
-- Antony Jay and Jonathan Lynn, "Yes Minister"
.

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