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12 pages

C++

C++23 introduces new features enumerate and ranges
Optimizing performance for a hot function involves the bulk of the time spent within internal loops. AI suggested using enumerate and ranges, so I consulted some related documentation. The main content of the article was generated by AI, and I tested the code and added some supplementary explanations. Online Compiler – testing C++ code inevitably involves our old friend. On gcc13, traditional for loops were slightly faster than std::views::enumerate, which

Cross-machine computation time difference

The existing communication protocol within the group uses steady_clock as a timestamp to calculate the latency for each individual node. In a specific scenario, a message packet’s built-in timestamp was used, and this timestamp originated from another machine – resulting in an anomalous latency calculation.

As a side note: Gemini2.5 Pro shows promise of completely surpassing GPT-4.

Memory Layout and Binary Compatibility

C++ service crashed. The service depends on a static library for compilation. The static library made modifications, adding members to the header file and re-publishing the binary static library file. The service relies on the new binary library file, compiles and runs normally, but then crashes. The crash point appears fine, similar to the crashes caused by compiler upgrades – undefined behavior, an untrustworthy stack trace. Updating the service’s dependent header files allows it to mutate correctly, and running also works normally. A detailed explanation is needed, involving computer science knowledge, I suspect it’s related to memory layout, with examples for a thorough explanation.

C++ Bitwise Operations Fundamentals: Bitwise Extraction and Flag Setting
In actual C++ development, bitwise operations are a common technique, especially when dealing with system states, flags, or control bits. Bitwise operations can provide very efficient solutions. This article will illustrate how to use bitwise operations to retrieve and set specific flags through an example. Bitwise Operations Fundamentals In computers, data is stored in binary bits (0 and 1). Bitwise operations are operations performed on these binary bits. C++ provides several commonly used bitwise operators:

Linux backend services handling large volumes of string data – performance is slow.
In the history of C++ development projects, we utilized a custom protocol for communication, which employed a two-dimensional array pattern. When processing large volumes of data, the protocol required iterating through the arrays and performing serialization operations to generate logs. Due to its low efficiency, this resulted in noticeable lag or stuttering within the system under heavy load, as reported by the business departments. Problem Identification When troubleshooting the issue, we first performed a performance analysis of the system and discovered that CPU utilization increased significantly when processing large amounts of data, and system response times became longer.

C++ Lambda Expression Parameter Lifetimes
In C++, lambda expressions are a convenient way to create anonymous functions that can capture external variables and use them within their bodies. This makes lambdas a flexible programming tool. However, the lifetime of parameters in a lambda expression is an aspect that requires careful attention, especially when capturing and passing parameters. 1. Lambda Expression Parameter Lifetime The lifetime of parameters in a lambda expression is typically the same as that of other C++ functions.

Upgrading the GCC version caused program crashes: hidden issues due to code non-compliance.
In the same business code scenario, the program compiled and ran normally in a CentOS 7 environment. However, when switching to CentOS 8 and using an updated version of GCC for compilation, the program crashed. It’s worth noting that the issue only occurs in Release mode, while Debug mode does not exhibit any problems. This is the first time we’ve encountered a situation like this; after three days of investigation, we finally identified the root cause.