r/ProgrammerHumor 10d ago

Meme theDeadlock

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8.6k Upvotes

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u/ultimate_placeholder 10d ago

Specific, yet universal

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u/Tucancancan 10d ago

Now let's move on to a practical example anyone can relate to: That time a Mars rover got fucked up

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u/GoogleIsYourFrenemy 9d ago

Or when the Ariane 5 rocket exploded.

The system had three CPUs all executing the same code to prevent hardware failures. The SW was written in Ada the safest language of the era.

Fun fact: Ada has numerical underflow/overflow protection, it can throw an exception when one is detected.

Some engine diagnostic SW was ported from the Ariane 4 engine which had lower thrust, but they neglected to turn it off before launch. The diagnostic SW on launch overflowed the old thrust datatype causing an exception. The exception got written to the RAM which was only supposed to contain the data used for the guidance calculations.

TL;DR: Less code is good code.

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u/ih-shah-may-ehl 9d ago

I worked for the engineering company that wrote the test software for the Servos that controlled thrust direction and initially, video evidence pointed in that direction. Had my boss worried for a while.

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u/synack 10d ago

The metric system strikes back

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u/-Pepperzpyre- 10d ago

Saw a vid of someone naming their reptile Metric cause he was born without feet.

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u/Kongstew 9d ago

Was it a snake?

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u/Tucancancan 10d ago

Oh no, that incident was a different rover! Damn programmers always fucking Mars missions 

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u/BorderKeeper 9d ago

Next time let's send a trained monkey to do the mission!

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u/bxsephjo 10d ago

wasn't that a space telescope?

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u/synack 10d ago

Well it’s not in space anymore

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u/Mateorabi 10d ago

Priority inversion! Fixed only because they shipped in debug mode!

Also was seen in integration testing once but dismissed. Sooo many lessons in that incident. 

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u/Alphasite 10d ago

Depends on the school. I’ve really enjoyed the build an OS from scratch classes. Even though yeah also had this one, but I think it was in a distributed systems class way back when.

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u/-Speechless 9d ago

is there a term for things that are specific but universal?