in switzerland you aren't allowed to have a train with exactly 256 axles because of an integer overflow in the axle counting machine

i wish i could fix my software bugs by making it illegal to cause them

the source everyone reports for this PDF is gone, and it's not exactly easy to find swiss train law documentation when you don't even speak german

but here's a current link:

page 123, section 4.8.4 "Zugbildung"

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die züge können keine 256 achsen haben! wie lächerlich!

"gnädige frau, das ist ein mcdonalds."

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@lynnesbian i mean, pretty much any security bug you might have is covered by law already

@Nikolai_Kingsley is is entirely possible that my two months of duolingo courses i did two years ago, combined with google translate, is not enough to produce a german sentence that doesn't sound weird


German is a good language. any language that has a single word that means "a face in search of a backhand" is a good language.


@Nikolai_Kingsley @lynnesbian it also forces you to binarily gender most nouns applied to a person (Backpfeifengesicht is an exception).

@lynnesbian 256 Achsen wären dann 64 4achsige Wagen - solche Züge gibt es nicht,

@lynnesbian But then a) You'd let everyone know how to break your software, and b) Unruly teens would constantly break your software, because of Crimes

@RedFuture ah but, it's illegal to break the law, so they simply would not do it

@RedFuture @lynnesbian gathering with my friends after school to build a train with exactly 256 axles, as a prank

@operand @lynnesbian Building a train with -1 axles to block out huge sections of track

There should be the same integer overflow at every multiple of 256 axles. There is a bug in the law.

@hambach18 i imagine that as soon as someone builds a train with that many axles they'll update the law

@lynnesbian proposed fix: mandate the ETD ( must be mounted on a little cart with 3 axles. Every train will need exactly one

@lynnesbian can't happen to us in Germany. We still have things like manual or mechanical operation of these things ;)

Only a fraction is electric ;)

@Drezil @lynnesbian you can still have an integer overflow in a mechanical counter. it's just more likely to be a decimal limit at rollover, not a binary one. automotive mechanical odometers were susceptible to this, as a 5+1 decimal digit mechanical counter. so you'd hit rollover at 100,000 DISTUNIT. my family has a car that's done it. our newer car has a digital Trip-O + Odometer with 6 digits, no tenths for the Odometer, just the Trip-O, so it'll hit rollover at 1,000,000 DISTUNIT


become a government. they're allowed to do whatever they want, like Googzilla or Microsofthra can

@chfo so they've either
a) fixed the issue
b) accidentally left the clause out
c) hoped everyone would stick to the rule anyway
d) haven't yet published the new law document that includes this clause


More about this one and a number other maths and computer sciece mistakes were also covered by a Matt Parker talk. (link is time-coded)

@lynnesbian it's like that xkcd comic where the guy named his kid DropTable.Student except better because it's real and involves trains

@lynnesbian Somewhere in Switzerland, there must be a 'ghost train' -- It has exactly 256 axles, so you never know it's coming, and you never know it's passed. Because there is only one, so long as it's extremely careful, it can avoid all collisions. Rarely seen, never recorded, and noone knows what it carries.

@lynnesbian Fixing problems by making them illegal does have an especially Swiss ring to it...

@zipheir @lynnesbian Not really, have you ever heard about DRM circumvention laws as an example?

@lynnesbian Oh hey! I'm the person who originally submitted this to reddit.

As far as I know, this rule is no longer in place. It still shows up in some recent-ish documents (like [1]), but a train driver I know showed me a screenshot of a document explicitly stating that this paragraph was made obsolete.

It also doesn't show up in the current R 300.5 anymore. [2]



@lynnesbian I think the original limitation was caused by mechanical counters with eight physical bits (so, not actually software), which have now been phased out.

@draemmli @lynnesbian
Otoh, the German LZB linear train control is 8-bit to its core. One sector is up to 12.7 km long, 127 × 100 m loop sections, for signed 8-bit position counters.

@draemmli thanks for clearing this up! i managed to find a slightly more recent document mentioning it, but you're right, it seems to have disappeared now

@lynnesbian In Switzerland you will never have a trains with 64 railway cars with 4 axles.

trans hate, state abuse 

This makes me think of the swedish law that forced transgendered people to be sterilized, and their semen/eggs to be destroyed.

The law was only removed in 2016 or so, long after the old "sterilize anyone that the nazis wouldn't want to breed" mentality went out of style.

No-one talked much about why they were still doing this, since the reasons were rather obvious. But I did find one person blaming paperwork.
"See, on this parenthood form, we have a mother square and a father square, and if you trans lot went and muddled it all up, the system would just break".

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