The Horror in the Standard Library

Post by marcosdumay » Sat, May 06, 2017, 2:36 PM UTC

kabdib wrote: post #53

bostik wrote: post #51

Earlier quoted context omitted.

> you can't trust libraries blindly, even one of the most used and broadly adopted ones There is a corollary to development and debugging. When things break in mysterious ways, we tend to go through a familiar song and dance. As experience, skills and even personal networks grow, we can find ourselves diving ever further in the following chain. 1. "It must be in my code." -- hours of debugging 2. "Okay, it must be so…

I've done the oscilloscope thing, though it was only a vanilla couple-of-hundred Mhz scope on some pins that were bugging me, and not the full deal: "Gang way, we're cracking the lid of that thing and going in." That sounds exciting, I'd love to see it. Once, I used a chunk of ice to cool down a chip, and that made it work. The hardware guys were unimpressed. But hey, they've got cans of Chill and they use them a lot…

Post by marcosdumay » Sat, May 06, 2017, 2:47 PM UTC

doubleplusgood wrote: post #67

bostik wrote: post #51

Earlier quoted context omitted.

> you can't trust libraries blindly, even one of the most used and broadly adopted ones There is a corollary to development and debugging. When things break in mysterious ways, we tend to go through a familiar song and dance. As experience, skills and even personal networks grow, we can find ourselves diving ever further in the following chain. 1. "It must be in my code." -- hours of debugging 2. "Okay, it must be so…

I feel lucky to only have reached item 4; I wouldn't feel confident beyond it, anyway.

Post by hackits » Sat, May 06, 2017, 2:53 PM UTC

SFJulie wrote: post #74

Memory fragmentation due to dynamic non fixed size data structure and multithreading is an old foe. That may not be fixable in c/c++ Worker A allocates dynamic stuff. Algo take a segment (0+sof(str)(ofA) + n) Work B Allocates to create same kind of data structure (fragment of a JSON) [ofA, OfB] Wk A resume allocating, boundary of [0, ofA] exceeded, no free contiguous space up or down [Ofb, OfC] allocated Wk C enters…

Post by mcguire » Sat, May 06, 2017, 2:55 PM UTC

marcosdumay wrote: post #121

kabdib wrote: post #53

Earlier quoted context omitted.

I've done the oscilloscope thing, though it was only a vanilla couple-of-hundred Mhz scope on some pins that were bugging me, and not the full deal: "Gang way, we're cracking the lid of that thing and going in." That sounds exciting, I'd love to see it. Once, I used a chunk of ice to cool down a chip, and that made it work. The hardware guys were unimpressed. But hey, they've got cans of Chill and they use them a lot…

At the late 90's and earlier 2000's it was commonplace to fix OS panics by opening the computer and pointing a fan at it. I would try it even before going for some harder software problems, because it's so easy.

Post by tomohawk » Sat, May 06, 2017, 3:04 PM UTC

saurik wrote: post #42

stephen_g wrote: post #35

Things like this is why I was happy to see the LLVM project write their own C++ standard library. libstdc++ has always seemed a bit hacky and fragile to me. It's great to have an option which is a more modern, clean codebase. Have you tested to see if this works better with LLVM libc++?

Alternatively, things like this is why it is great when everyone works together to improve one lib rather instead of forming their efforts on two essentially-identical ones. You act like libc++ is somehow simply better and probably doesn't have bugs :/. I have been doing C++ work now for over two decades and let me set that record straight in your head: incredibly basic stuff has been pretty extremely broken in libc+…