Re: what does two semicolns ';;' do

Iv??n S??nchez Ortega <ivansanchez-alg@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
Thomas Mlynarczyk wrote:

jimp@xxxxxxxxxxxxxxxxxxxx schrieb:

AIR for(;;) is slightly more efficient/faster than while(1).

How come? Isn't [for] just syntactic sugar for [while] and should
therefore internally be the same?

It really depends on how your compiler optimizes jumps and boolean
expressions. A good compiler will know that both while(1) and for(;;) are
infinite loops and will translate them to non-conditional jumps in
assembler, effectively rendering them the same.

A bad compiler won't.

And some compilers will recognize one but not the other.


--
Jim Pennino

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