A program crashed during shutdown, with message pure virtual method called which came from __cxa_pure_virtual – where a pure virtual function points to, in its vtable. Its implementation involves calling std::terminate which calls std::abort which by default throws a SIGABRT, and crashing the program. Now, why did…
Lifetime in many ways are similar to types but also different. The goal of this post is to explain my mental model of rust's lifetime binding works, when it takes place, and a trick to force late lifetime binding when needed. Here's a motivating example that I will use throughout…
I use zsh and yesterday I was testing a program with myprogram 2>/dev/null. In one iteration, I accidentally copied a newline character after the myprogram command and the zsh prompt looked something like $ myprogram 2>/dev/null The program appeared to hang after printing out the expected output.…
We rarely need to worry about lambda's lifetime more than any other objects in C++ until we are dealing with coroutine at the same time. folly's wiki has a good example of why we need to be careful about lambda's lifetime – https://github.com/facebook/folly/blob/main/folly/experimental/…
I see folly::IOBuf often used as a return value (sub-)type in RPC definitions for data intensive and high performance applications. I looked at the code, and it says Well if it's used primarily for networking code, why do applications use it? I don't think people use sk_buff…
C++'s inline is pretty nice, in my opinion. I define an inline function with external linkage, things work as expected (https://en.cppreference.com/w/cpp/language/inline): * taking the address of the inline function works * function-local static objects work as expected (shared across all translation units) * no ODR…
I have eero at home with eero plus subscription as I like the parental controls. To my delight, the subscription also comes with DDNS. I wanted to set it up so I can ssh to my workstation from a laptop from our town library or a coffee shop. 1. Enabled…
Here is the section 3.5 of Nancy Lynch's 1989 paper – A Hundred Impossibility Proofs for Distributed Computing, which is profound: What good are impossibility results, anyway? They don't seem very useful at first, since they don't allow computers to do anything they couldn't previously. Most obviously, impossibility results tell…