C++20, Spans, Threads and Fun -- Bartlomiej Filipek

C++20_Spans_Threads_and_Fun.pngIn this post, we’ll have fun using C++20’s spans to process data on multiple threads. What’s more, we’ll be equipped with the latest concurrency features from C++20.

C++20, Spans, Threads and Fun

by Bartlomiej Filipek

From the article:

Our task is relatively simple but can be extended to various multi-phase computations.

We need to initialize a container with numbers, filter them, then build a histogram.

Here’s the overview of the process:

CLion Nova Explodes onto the C and C++ Development Scene -- Anastasia Kazakova

clionnova.pngWe’re announcing a free early preview of CLion, which uses the ReSharper C++/Rider C++ language engine instead of the CLion "legacy" engine. The Preview build is available via our dedicated Toolbox App feed. At some point in 2024, depending on the results of the feedback collected, CLion Nova will be merged into CLion. Until then, the Preview build will be free to use and can be installed in parallel with your usual CLion (Classic) installation.

CLion Nova Explodes onto the C and C++ Development Scene

by Anastasia Kazakova

From the article:

The first C++ engine by JetBrains was designed for AppCode, our IDE for iOS and macOS developers. It was part of the IntelliJ Platform, initially written in Java and later also in Kotlin. The approach and the architecture of the engine serve many languages in IntelliJ-based IDEs well; however, this design turned out not to be the best fit for the C++ language specifically.

To more quickly align with the evolution of C++ and to separate the engine and IDE processes, a clangd-based engine was later added to CLion. Built on our custom branch of clangd, this engine detects any warnings and errors, shows them in the editor, and suggests quick-fixes, as well as performing highlighting, completion, and certain navigation actions. It’s also used for things like data flow analysis and MISRA checks. Meanwhile, CLion’s “legacy” engine is responsible for other code insight features like refactorings. You can see a detailed “list of responsibilities” in our CLion documentation.

Top 10 errors in C and C++ projects in 2023

New Year is coming! It means, according to tradition, it's time to recall 10 of the most interesting bugs that PVS-Studio found during 2023.

Top 10 errors in C and C++ projects in 2023

by Alexey Gorshkov

From the article:

In this case, the developers wanted to fill the keyEventList array with zeros. Pay attention to the third parameter — the number of bytes the developers wanted to fill with zeros. In this case, sizeof(keyEventList) evaluates the pointer size instead of the array size. It depends on the target platform, but most often it's 4 or 8 bytes. However, the size of the structure is clearly larger than 4 or 8 bytes.

How Can I Prevent Myself From Using a Parameter After I’ve Extracted All Value? -- Raymond Chen

Imagine you have a function parameter that you want to protect from direct access, ensuring that all future interactions occur through a wrapper or transformation. This situation often arises in scenarios like implementing a logging wrapper for a class. In this discussion, we'll explore a clever technique known as "hide_name" to achieve this goal, allowing you to enforce the use of the wrapper and prevent direct access to the parameter.

How Can I Prevent Myself From Using a Parameter After I’ve Extracted All Value From It?

By Raymond Chen

From the article:

Suppose you have a function that takes a parameter that you want to transform in some way, and you want to require that all future access to the parameter be done through the transformed version. One example is a wrapper class that does logging.¹

struct WidgetRefWrapper
{
    WidgetRefWrapper(
        Widget& widget,
        Logger& logger) :
    m_widget(widget), m_logger(logger) {}
    
    void Toggle() try
    {
        m_logger.Log("Toggling the widget");
        m_widget.Toggle();
        m_logger.Log("Toggled the widget");
    } catch (...) {
        m_logger.Log("Exception while toggling the widget");
        throw;
    }

private:
    Widget& m_widget;
    Logger& m_logger;
};

void DoSomething(Widget& widget)
{
    Logger& logger = GetCurrentLogger();
    WidgetWrapper wrapper(widget, logger);

    // Do not use the widget directly!
    // Always use the wrapper!

    if (needs_toggling) {
        wrapper.Toggle();
    }
}

You want that “Do not use the widget directly!” comment to have some teeth. Can you “poison” the widget parameter so it cannot be used any more?

PVS-Studio 7.28: support for ARM, analysis of Unreal Engine projects without Unity Build, and more

Now you can run the analyzer on the ARM architecture, analyze .NET 8 projects, and check Unreal Engine projects without Unity Build — and there is more to come.

PVS-Studio 7.28: support for ARM, .NET 8, analysis of Unreal Engine projects without Unity Build, and more

by Gleb Aslamov

From the article:

When analyzing Unreal Engine projects with PVS-Studio, we often encounter issues with high memory usage and analysis slowdown. They usually arise when individual translation units are combined into a single file (the Unity Build system). Although the merging of translation units may have a positive impact on the compilation time, the large file size may increase the resource requirements for analysis.