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Does memory leak? (1995)

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Re: Does memory leak? (1995)

#91

Post by 0xffff2 »

giu wrote: post #85
jakeinspace wrote: post #69

As somebody working on embedded software for aerospace, I'm surprised this missile system even had dynamic memory allocation. My entire organization keeps flight-critical code fully statically allocated.

I'm always fascinated about software running on hardware-restricted systems like planes, space shuttles, and so on. Where can someone (i.e., in my case a software engineer who's working with Kotlin but has used C++ in his past) read more about modern approaches to writing embedded software for such systems? I'm asking for one because I'm curious by nature and additionally because I simply take the garbage collector f…

The embedded world is very slow to change, so you can read about "modern approaches" (i.e. approaches used today) in any book about embedded programming written in the last 30 years.

I currently work on spacecraft flight software and the only real advance on this project over something like the space shuttle that I can point to is that we're trying out some continuous integration on this project. We would like to use a lot of modern C++ features, but the compiler for our flight hardware platform is GCC 4.1 (upgrading to GCC 4.3 soon if we're lucky).

Re: Does memory leak? (1995)

#92

Post by GuB-42 »

GordonS wrote: post #42

A bit OT, but I wonder how I'd feel if I was offered a job working on software for missiles. I'm sure the technical challenge would be immensely interesting, and I could tell myself that I cared more about accuracy and correctness than other potential hires... but from a moral standpoint, I don't think I could bring myself to do it. I realise of course that the military uses all sorts of software, including line of b…

There are different kinds of killing machines. And accurate missiles are among the least bad.

With the exception of nuclear weapons (that's another topic), missiles are designed to destroy one particular target of strategic importance and nothing more. They are too expensive as mass killing weapons, but they are particularly appropriate for defense.

Without missiles, you may need to launch an assault, destroying everything on your way to the target, risk soldier lives, etc... Less accurate weapons mean higher yield to compensate, so more needless destruction.

War is terrible, but I'd rather have it fought with missiles than with mass produced bombs, machine guns, and worst of all, mines.

Re: Does memory leak? (1995)

#93

Post by Razengan »

jmpman wrote: post #71
GordonS wrote: post #42

A bit OT, but I wonder how I'd feel if I was offered a job working on software for missiles. I'm sure the technical challenge would be immensely interesting, and I could tell myself that I cared more about accuracy and correctness than other potential hires... but from a moral standpoint, I don't think I could bring myself to do it. I realise of course that the military uses all sorts of software, including line of b…

Straight out of college, I was offered a job writing software for missiles. Extremely interesting area, working for my adjunct professor’s team, who I highly admired and whose class was the best of my college career. The pay was on par with all my other offers. I didn’t accept for two reasons. First, I logically agreed that the missiles were supporting our armed services and I believed that our government was general…

> he pulled me aside and sternly instructed “You should never repeat that story”

We really need more exposure for the things that people like that want to silence..

Re: Does memory leak? (1995)

#94

Post by jakeinspace »

saagarjha wrote: post #90
giu wrote: post #85

Earlier quoted context omitted.

I'm always fascinated about software running on hardware-restricted systems like planes, space shuttles, and so on. Where can someone (i.e., in my case a software engineer who's working with Kotlin but has used C++ in his past) read more about modern approaches to writing embedded software for such systems? I'm asking for one because I'm curious by nature and additionally because I simply take the garbage collector f…

Searching for things like "MISRA C" and "real-time computing" will help you get started.

My older co-workers have some great alternative definitions of that initialism.

Re: Does memory leak? (1995)

#95

Post by giu »

saagarjha wrote: post #90
giu wrote: post #85

Earlier quoted context omitted.

I'm always fascinated about software running on hardware-restricted systems like planes, space shuttles, and so on. Where can someone (i.e., in my case a software engineer who's working with Kotlin but has used C++ in his past) read more about modern approaches to writing embedded software for such systems? I'm asking for one because I'm curious by nature and additionally because I simply take the garbage collector f…

Searching for things like "MISRA C" and "real-time computing" will help you get started.

Thanks a lot for the keywords; these are very good starting points to look for further stuff on the topic!

Didn't know that there was a term (i.e., real-time computing) for this kind of systems / constraints.

Re: Does memory leak? (1995)

#96

Post by jnwatson »

jmpman wrote: post #71
GordonS wrote: post #42

A bit OT, but I wonder how I'd feel if I was offered a job working on software for missiles. I'm sure the technical challenge would be immensely interesting, and I could tell myself that I cared more about accuracy and correctness than other potential hires... but from a moral standpoint, I don't think I could bring myself to do it. I realise of course that the military uses all sorts of software, including line of b…

Straight out of college, I was offered a job writing software for missiles. Extremely interesting area, working for my adjunct professor’s team, who I highly admired and whose class was the best of my college career. The pay was on par with all my other offers. I didn’t accept for two reasons. First, I logically agreed that the missiles were supporting our armed services and I believed that our government was general…

Sticking with a vendor even though they are very late is quite common among even non-government programs.

Big projects are hard and they are frequently late. The fact that it is for the government is largely besides the point.

Re: Does memory leak? (1995)

#97

Post by rowanG077 »

0xffff2 wrote: post #91
giu wrote: post #85

Earlier quoted context omitted.

I'm always fascinated about software running on hardware-restricted systems like planes, space shuttles, and so on. Where can someone (i.e., in my case a software engineer who's working with Kotlin but has used C++ in his past) read more about modern approaches to writing embedded software for such systems? I'm asking for one because I'm curious by nature and additionally because I simply take the garbage collector f…

The embedded world is very slow to change, so you can read about "modern approaches" (i.e. approaches used today) in any book about embedded programming written in the last 30 years. I currently work on spacecraft flight software and the only real advance on this project over something like the space shuttle that I can point to is that we're trying out some continuous integration on this project. We would like to use…

I find it interesting that such critical code is written in C. Why not use something with a lot more (easily)statically provable properties. Like Rust or Agda?

Re: Does memory leak? (1995)

#98

Post by jpmattia »

GordonS wrote: post #42

A bit OT, but I wonder how I'd feel if I was offered a job working on software for missiles. I'm sure the technical challenge would be immensely interesting, and I could tell myself that I cared more about accuracy and correctness than other potential hires... but from a moral standpoint, I don't think I could bring myself to do it. I realise of course that the military uses all sorts of software, including line of b…

> but from a moral standpoint, I don't think I could bring myself to do it.

I've been in a similar situation, and I think there is something important to think about: Assuming you'd be working for the defense of a country with a track record of decency (at least a good fraction of the time anyway), you have to decide what people you want taking those jobs.

Is it better that all of the people with qualms refuse to take the positions? ie Do you want that work being done by people with no qualms? Because that sounds pretty terrible too.

Re: Does memory leak? (1995)

#99

Post by MiroF »

rowanG077 wrote: post #97
0xffff2 wrote: post #91

Earlier quoted context omitted.

The embedded world is very slow to change, so you can read about "modern approaches" (i.e. approaches used today) in any book about embedded programming written in the last 30 years. I currently work on spacecraft flight software and the only real advance on this project over something like the space shuttle that I can point to is that we're trying out some continuous integration on this project. We would like to use…

I find it interesting that such critical code is written in C. Why not use something with a lot more (easily)statically provable properties. Like Rust or Agda?

Because safety critical fields are also slow-moving.

Re: Does memory leak? (1995)

#100

Post by stefan_ »

tyingq wrote: post #4

Until the cruise missile shop down the hall decides to reuse your controller.

Remember when the CIA contracted with Netezza to improve their predator drone targeting, who then went and reverse-engineered some software from their ex business partner IISI and shipped that?

IISi’s lawyers claimed on September 7, 2010 that “Netezza secretly reverse engineered IISi’s Geospatial product by, inter alia, modifying the internal installation programs of the product and using dummy programs to access its binary code [ … ] to create what Netezza’s own personnel reffered to internally as a “hack” version of Geospatial that would run, albeit very imperfectly, on Netezza’s new TwinFin machine [ … ] Netezza then delivered this “hack” version of Geospatial to a U.S. Government customer (the Central Intelligence Agency) [ … ] According to Netezza’s records, the CIA accepted this “hack” of Geospatial on October 23, 2009, and put it into operation at that time.”

Reality is always more absurd, government agencies remain inept and corrupt even when shrouded in secrecy to cover up their missteps, and by the way, Kubernetes now flies on the F16.

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