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SubjectRe: [BUG] Bad #define, nonportable C, missing {}
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Vincent Sweeney <v.sweeney@dexterus.com> writes:

|> vda wrote:
|> > ------------------------------------------------------------------
|> > Undefined behavior by C std: inc/dec may happen before dereference.
|> > Probably GCC is doing inc after right side eval, but standards say nothing
|> > about it AFAIK. Move ++ out of the statement to be safe:
|> > *a++ = byte_rev[*a]; => *a = byte_rev[*a]; a++;
|>
|> C std says *always* evaluate from right to left for = operators, so this
|> will always make perfect sense.

No. It is undefined which of the operator's arguments is evaluated first,
unless it is defined otherwise (only for ||, && and comma).

Andreas.

--
Andreas Schwab "And now for something
Andreas.Schwab@suse.de completely different."
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