Posts

Patterns for constructing reference-counted objects: Factory functions vs `as` operator

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The construction of reference-counted object instances, which have automatic memory management, is a recurring topic. The main problem with such instances is that they need to be assigned to an interface reference (explicit or implicit) to have a properly initialized reference counting mechanism and a properly managed lifetime. There are many different coding patterns and scenarios around the construction and assignment of such instances. The simplest scenario is having an explicit interface reference to which we will assign the newly constructed object; in some, the compiler will lend us a hand and insert the appropriate code behind the scenes; and in some, it will do the opposite, due to either some compiler bugs or an ambiguity in the code which cannot be automatically resolved by the compiler. In previous blog posts, I have previously covered some such scenarios which needed special attention from developers to avoid bugs: Hello Old New Leaky Friend Inline Variables Type I...
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Delphi 12.3 Update

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The Delphi 12.3 update has just been released. The most exciting part of this release is the long-awaited 64-bit IDE. Now, this is only an Initial Release of the IDE, and it is not yet a full replacement for the 32-bit IDE and its functionality. The main advantage of the 64-bit IDE is that the available memory is no longer constrained by the 32-bit address space, and the upper limit is now the available system memory. The more you have, the more you can use. This is a great news for all developers with large projects, where the 32-bit IDE would easily hit the memory wall. To start with, the 64-bit IDE only supports the 64-bit Windows platform. The primary purpose of such a release with only partial functionality is to allow all component developers to update their design-time packages, and prepare them to support the 64-bit IDE. And to do that, you only need the 64-bit Windows platform anyway. For all other platforms, there is no immediate advantage of using a 64-bit IDE. As we all...
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Stack Overflow: A year in moderation

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On the 13th March, last year I was elected as a Stack Overflow moderator. I am using this opportunity to thank everyone who who voted for me back then. It has been an interesting year. The "Chinese curse" kind of interesting, but I can't talk about that too much. The world is flooded with AI slop, and everyone and their dog is using it. And Stack Overflow users are no exception. Low-reputation users, high-reputation users, the magical song of AI is too hard to resist. Literal thousands and thousands of users have posted AI answers, thinking they will get away with it. Thousands and thousands have failed. When someone asks me why am I so skeptical about AI? The answer is really simple: I have seen it all. I know what it can and what it cannot do. And while it is certainly a useful tool when used carefully and for specific purposes, most of the time it is a huge time waster. Responsible use of AI is a rare occurrence on the site. I think I can count the number of case...
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Celebrating 30 Years of Delphi With a New Book: Delphi Quality-Driven Development

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This year, on February 14th, Delphi celebrates its 30th birthday. Over the past three decades, Delphi has proven to be a robust and versatile development environment, empowering developers to build high-performance applications with ease across multiple platforms: Windows, Linux, Android, iOS, and macOS.  As we commemorate this milestone, I am also introducing a new book to help guide you into Delphi's fourth decade: Delphi Quality-Driven Development. Useful to lone developers and vast teams alike, this book aims to demonstrate a variety of essential practices and techniques for making high-quality, testable code. There is a 25% sale going on until the end of February for the Delphi Quality-Driven Development ebook, and there you can also get an additional discount on other books if you add them to your order. To all my fellow Delphi developers: May your code compile quickly, your memory be manageable, and your code testable.   Delphi Quality-Driven Development Book A practica...
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Hello Old New Leaky Friend

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Developers that extensively use interfaces in Delphi probably know about a long-standing issue with the compiler, where interface parameters declared as const or [ref] will cause a memory leak if a reference-counted object instance is constructed directly at the call site. Illustration: Sandra Prasnikar        Specifically, the following code would create a leak: procedure LeakTest(const Intf: IInterface); begin end; procedure Run; begin LeakTest(TInterfacedObject.Create); end; begin ReportMemoryLeaksOnShutdown := True; Run; end. The problem arises because the compiler does not create a hidden interface reference that would properly initialize the reference counting mechanism and keep the object instance alive during the call. In other words, such an object would never be assigned to a strong interface reference. Because const and [ref] parameters don't trigger reference counting, if there is no other code within the called routine, the obj...
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Delphi 12.1 & New Quality Portal Released

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The Delphi 12.1 update has been released. Besides a number of bug fixes, this release also has a few new features. The most notable ones are the new Split Editor, which allows having multiple files opened side by side; and support for Android API 34. You can find more information about what is new in this update at https://docwiki.embarcadero.com/RADStudio/Athens/en/12_Athens_-_Release_1 However, the greatest change for all Delphi developers is a new bug tracking portal that replaces the old one, still available in read-only mode at https://quality.embarcadero.com/ . The new portal is hosted in Atlassian Cloud https://embt.atlassian.net/servicedesk/customer/portals  or through a redirect https://qp.embarcadero.com and is based on Jira Service Management (JSM), while the internal bug tracking system, which was also migrated to the cloud, was not changed and is running on Jira. This move to the cloud was inevitable, because Atlassian retired their Server line of products. JSM i...
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Catch Me If You Can - Part II

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It has been quite some time since I wrote the Catch Me If You Can post about the inability of LLVM-backed compilers to catch non-call hardware exceptions. In other words, hardware exceptions raised by code written in the same block as the try...except exception handler. Since then, more LLVM-backed compilers have been added to Delphi, and with those, more reasons to change common coding practices... but still, very few developers know about the issue. The original article covered only try...except exception handlers, and exploring what exactly happens with implicit and explicit try...finally handlers was left as an exercise to the readers and to some future, now long overdue, post. And Now: All Hell Breaks Loose When you read about non-call hardware exceptions not being caught by an immediate try...except block, the implications might not look too serious. After all, while plenty of code can raise exceptions, try...except handlers are not that frequently used in places, as mo...
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