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A comment on The C++ standard for the F-35 Fighter Jet [video]. Parent comment

Re:The C++ standard for the F-35 Fighter Jet [video] by coppsilgold on Sunday December 07, 2025 @08:16PM (#46187219)
> This can be bad if a particular memory cell has failed. If every variable has a fixed address, and one of those addresses goes bad, a patch can be loaded to move that address and the mission can continue.

This seems like a rather manual way to go about things for which an automated solution can be devised. Such as create special ECC memory where you also account for entire cell failure with Reed-Solomon coding or some boot process which blacklists bad cells etc.

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Re:The C++ standard for the F-35 Fighter Jet [video] by j16sdiz on Monday December 08, 2025 @01:47AM (#46189186)
It is more than that.

This is what make remote debugging possible. It is impossible to do interactive remote debugging over a ultra low bandwidth link. If everything have static address and deterministic static, you can have a exact copy on ground and debug there.

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Re:The C++ standard for the F-35 Fighter Jet [video] by varjag on Monday December 08, 2025 @03:23AM (#46189748)
Interactive debugging is apparently possible and was reportedly done on Deep Space One mission. One of developers involved frequents HN I believe.
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Re:The C++ standard for the F-35 Fighter Jet [video] by unloader6118 on Monday December 08, 2025 @05:29AM (#46190689)
Kind of. That took hours of not days.

A local exact replica with deterministic state save lots of time.

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Re:The C++ standard for the F-35 Fighter Jet [video] by coppsilgold on Monday December 08, 2025 @12:55PM (#46195413)
> If everything have static address and deterministic static, you can have a exact copy on ground and debug there.

You can also have deterministic dynamic - the satellite could transmit its dynamic state (a few bits signifying which memory cells failed) and then you proceed deterministically on the ground.

[ Parent | on HN ]