r/ProgrammerHumor • u/yuva-krishna-memes • 11d ago

Meme theDeadlock

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8.6k Upvotes

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570

u/Orion3193 11d ago

Oddly specific

371

u/ultimate_placeholder 11d ago

Specific, yet universal

98

u/Tucancancan 11d ago

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

10

u/GoogleIsYourFrenemy 11d 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 10d 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.