Crash-free user sessions went down from almost 100% to 96% in a few months. Once the number of these issues started increasing we started getting more and more nervous. The content of the issues was not helpful, because where it crashes has little relation to where the real problem is. It all started with reports from Crashlytics about an increasing number of heap corruption issues. a hard crash) can happen later, when the program tries to manipulate the incorrectly allocated piece of memory, the root cause of the issue can remain hidden from your eyes. Typical heap corruption problems are reading, or writing outside of the bounds of allocated memory, or double-freeing memory. Heap corruption occurs when dynamic allocation of memory is not handled properly. First, let’s have a look at what heap corruption is After sharing a few tweets about it on Twitter, I had a lot of people asking me for more details, so here I am, sharing the story of the mighty heap corruption issue.Īre you ready for a tale of woe, frustration, and ultimately, redemption? Are you curious about how other iOS teams - ours, in this case - investigate and track down bugs? Read on.
The crashes were marked as heap corruption, which makes them hard to debug - the location given in the stack trace (if any) can be far away in both code and time to where the problem actually lies.Īfter a long investigation down many paths, it turned out to be an issue in Swift itself. The longtime adversaries return to Deep Space Nine with an uncomfortable new aspect to their relationship - the fact that Quark saved Odo's life.A while back, we noticed an increase in crashes in our app. Defiant - where Bashir, Dax, and Worf inform him that Quark indeed made it to the top and was able to signal for help. As Odo prepares to do the same, he is suddenly transported off the mountain. But when night falls, Odo is still alone, assuming that Quark failed to reach his goal and died. After Odo tries to take the transmitter himself, broken leg and all, Quark is shamed into resuming his attempt. Odo insists that Quark leave him behind andcontinue alone to the top, but Quark, exhausted and hungry, is ready to give up. Quark tries to drag Odo up the mountain, but is soon proves to be too much work for him.
While Quark is unhurt, Odo's leg is broken. Words soon escalate into a shoving match, and they wind up sliding down the mountainside. The pair argues throughout the journey, even as they finally begin to climb the mountain. With no other choice, Quark and Odo make their way down into the valley toward the mountain. As they clear the trees, they come to the edge of a steep cliff overlooking a deep valley. Quark is ready to give up when Odo encourages him with an estimate of six hours before reaching the top of the mountain. Sharing one set of cold-weather gear between them, they make their way toward the mountain, bickering all the way. Taking the runabout's subspace transmitter, he suggests they haul the heavy piece of equipment up an enormous mountain, where the atmosphere may be thin enough to send a signal for help. They are left with a horrifying choice - starve to death or freeze to death - when Quark has an idea. Forced to crash-land on a frozen, desolate planet, Odo and Quark learn that they lost their communications system, their replicator, and most of their rations in the explosion. They contain the explosion in a transporter beam, but the runabout is still severely damaged. When he and Odo investigate, they find a bomb aboard the runabout. Halfway to their destination, Quark hears a strange buzzing noise. Odo is dispatched to escort Quark to a Federation Grand Jury hearing, an eight-day journey away.