Question: A few minutes ago, a [question about *"double compilation"*](https://stackoverflow.com/q/24965167/2344584) was posted. The OP read an article claiming that passing an already compiled executable through GCC for a second time results in a 2x speed boost and asked how that was possible.

Double compilation is clearly impossible and the article is likely to be a hoax. But I realize that it might not be obvious to newbies, so I am uncertain whether:

1. I should vote to close the question as off-topic for SO
2. the question should be left open for people to learn about the hoax.

So, should I vote to close the question or leave it open?

Answer: 
Whether or not the article exists the hoax/mistake is circulating. Otherwise the person asking the question would not have heard it.

It's worth debunking such obviously false claims, whether backed by an article or not...as we don't know how far the false information may have spread.

(Obviously something as ludicrous as that would not spread far as anyone who knows anything about how compilers work would be able to immediately spot it as false but other invalid claims are far more reasonable on the surface).
It's a similar case to [Which is faster: while(1) or while(2)?](https://stackoverflow.com/questions/24848359/which-is-faster-while1-or-while2)

Such questions should exist on SO, just to provide the reference to the future visitors that it's a hoax. A hoax must be demented publicly, because otherwise anyone googling for that hoax would find only the sites that "prove" it. 

It's not hard to believe, even for an advanced programmer, that some tool may give better result when run second time. Unfortunately, the tools that give the other output each time they are run, or even are unable to run correctly at the first time, are getting more and more the normality.