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Native Git version with Apple Build
By default, it seems 15.6 is shipped with git version 2.39.5 (Apple Git-154) I was wondering when Apple will ship a Git version above 2.43 to resolve this vulnerability. Git Carriage Return Line Feed (CRLF) Vulnerability (CVE-2025-48384) https://github.com/git/git/security/advisories/GHSA-vwqx-4fm8-6qc9 You can install Homebrew then install newer versions of git using Homebrew; however that installs in a new location so the vulnerability is still present as the native version is behind and updated by Apple during software updates Thanks
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Aug ’25
An Apple Library Primer
Apple’s library technology has a long and glorious history, dating all the way back to the origins of Unix. This does, however, mean that it can be a bit confusing to newcomers. This is my attempt to clarify some terminology. If you have any questions or comments about this, start a new thread and tag it with Linker so that I see it. Share and Enjoy — Quinn “The Eskimo!” @ Developer Technical Support @ Apple let myEmail = "eskimo" + "1" + "@" + "apple.com" An Apple Library Primer Apple’s tools support two related concepts: Platform — This is the platform itself; macOS, iOS, iOS Simulator, and Mac Catalyst are all platforms. Architecture — This is a specific CPU architecture used by a platform. arm64 and x86_64 are both architectures. A given architecture might be used by multiple platforms. The most obvious example of this arm64, which is used by all of the platforms listed above. Code built for one platform will not work on another platform, even if both platforms use the same architecture. Code is usually packaged in either a Mach-O file or a static library. Mach-O is used for executables (MH_EXECUTE), dynamic libraries (MH_DYLIB), bundles (MH_BUNDLE), and object files (MH_OBJECT). These can have a variety of different extensions; the only constant is that .o is always used for a Mach-O containing an object file. Use otool and nm to examine a Mach-O file. Use vtool to quickly determine the platform for which it was built. Use size to get a summary of its size. Use dyld_info to get more details about a dynamic library. IMPORTANT All the tools mentioned here are documented in man pages. For information on how to access that documentation, see Reading UNIX Manual Pages. There’s also a Mach-O man page, with basic information about the file format. Many of these tools have old and new variants, using the -classic suffix or llvm- prefix, respectively. For example, there’s nm-classic and llvm-nm. If you run the original name for the tool, you’ll get either the old or new variant depending on the version of the currently selected tools. To explicitly request the old or new variants, use xcrun. The term Mach-O image refers to a Mach-O that can be loaded and executed without further processing. That includes executables, dynamic libraries, and bundles, but not object files. A dynamic library has the extension .dylib. You may also see this called a shared library. A framework is a bundle structure with the .framework extension that has both compile-time and run-time roles: At compile time, the framework combines the library’s headers and its stub library (stub libraries are explained below). At run time, the framework combines the library’s code, as a Mach-O dynamic library, and its associated resources. The exact structure of a framework varies by platform. For the details, see Placing Content in a Bundle. macOS supports both frameworks and standalone dynamic libraries. Other Apple platforms support frameworks but not standalone dynamic libraries. Historically these two roles were combined, that is, the framework included the headers, the dynamic library, and its resources. These days Apple ships different frameworks for each role. That is, the macOS SDK includes the compile-time framework and macOS itself includes the run-time one. Most third-party frameworks continue to combine these roles. A static library is an archive of one or more object files. It has the extension .a. Use ar, libtool, and ranlib to inspect and manipulate these archives. The static linker, or just the linker, runs at build time. It combines various inputs into a single output. Typically these inputs are object files, static libraries, dynamic libraries, and various configuration items. The output is most commonly a Mach-O image, although it’s also possible to output an object file. The linker may also output metadata, such as a link map (see Using a Link Map to Track Down a Symbol’s Origin). The linker has seen three major implementations: ld — This dates from the dawn of Mac OS X. ld64 — This was a rewrite started in the 2005 timeframe. Eventually it replaced ld completely. If you type ld, you get ld64. ld_prime — This was introduced with Xcode 15. This isn’t a separate tool. Rather, ld now supports the -ld_classic and -ld_new options to select a specific implementation. Note During the Xcode 15 beta cycle these options were -ld64 and -ld_prime. I continue to use those names because the definition of new changes over time (some of us still think of ld64 as the new linker ;–). The dynamic linker loads Mach-O images at runtime. Its path is /usr/lib/dyld, so it’s often referred to as dyld, dyld, or DYLD. Personally I pronounced that dee-lid, but some folks say di-lid and others say dee-why-el-dee. IMPORTANT Third-party executables must use the standard dynamic linker. Other Unix-y platforms support the notion of a statically linked executable, one that makes system calls directly. This is not supported on Apple platforms. Apple platforms provide binary compatibility via system dynamic libraries and frameworks, not at the system call level. Note Apple platforms have vestigial support for custom dynamic linkers (your executable tells the system which dynamic linker to use via the LC_LOAD_DYLINKER load command). This facility originated on macOS’s ancestor platform and has never been a supported option on any Apple platform. The dynamic linker has seen 4 major revisions. See WWDC 2017 Session 413 (referenced below) for a discussion of versions 1 through 3. Version 4 is basically a merging of versions 2 and 3. The dyld man page is chock-full of useful info, including a discussion of how it finds images at runtime. Every dynamic library has an install name, which is how the dynamic linker identifies the library. Historically that was the path where you installed the library. That’s still true for most system libraries, but nowadays a third-party library should use an rpath-relative install name. For more about this, see Dynamic Library Identification. Mach-O images are position independent, that is, they can be loaded at any location within the process’s address space. Historically, Mach-O supported the concept of position-dependent images, ones that could only be loaded at a specific address. While it may still be possible to create such an image, it’s no longer a good life choice. Mach-O images have a default load address, also known as the base address. For modern position-independent images this is 0 for library images and 4 GiB for executables (leaving the bottom 32 bits of the process’s address space unmapped). When the dynamic linker loads an image, it chooses an address for the image and then rebases the image to that address. If you take that address and subtract the image’s load address, you get a value known as the slide. Xcode 15 introduced the concept of a mergeable library. This a dynamic library with extra metadata that allows the linker to embed it into the output Mach-O image, much like a static library. Mergeable libraries have many benefits. For all the backstory, see WWDC 2023 Session 10268 Meet mergeable libraries. For instructions on how to set this up, see Configuring your project to use mergeable libraries. If you put a mergeable library into a framework structure you get a mergeable framework. Xcode 15 also introduced the concept of a static framework. This is a framework structure where the framework’s dynamic library is replaced by a static library. Note It’s not clear to me whether this offers any benefit over creating a mergeable framework. Earlier versions of Xcode did not have proper static framework support. That didn’t stop folks trying to use them, which caused all sorts of weird build problems. A universal binary is a file that contains multiple architectures for the same platform. Universal binaries always use the universal binary format. Use the file command to learn what architectures are within a universal binary. Use the lipo command to manipulate universal binaries. A universal binary’s architectures are either all in Mach-O format or all in the static library archive format. The latter is called a universal static library. A universal binary has the same extension as its non-universal equivalent. That means a .a file might be a static library or a universal static library. Most tools work on a single architecture within a universal binary. They default to the architecture of the current machine. To override this, pass the architecture in using a command-line option, typically -arch or --arch. An XCFramework is a single document package that includes libraries for any combination of platforms and architectures. It has the extension .xcframework. An XCFramework holds either a framework, a dynamic library, or a static library. All the elements must be the same type. Use xcodebuild to create an XCFramework. For specific instructions, see Xcode Help > Distribute binary frameworks > Create an XCFramework. Historically there was no need to code sign libraries in SDKs. If you shipped an SDK to another developer, they were responsible for re-signing all the code as part of their distribution process. Xcode 15 changes this. You should sign your SDK so that a developer using it can verify this dependency. For more details, see WWDC 2023 Session 10061 Verify app dependencies with digital signatures and Verifying the origin of your XCFrameworks. A stub library is a compact description of the contents of a dynamic library. It has the extension .tbd, which stands for text-based description (TBD). Apple’s SDKs include stub libraries to minimise their size; for the backstory, read this post. Use the tapi tool to create and manipulate stub libraries. In this context TAPI stands for a text-based API, an alternative name for TBD. Oh, and on the subject of tapi, I’d be remiss if I didn’t mention tapi-analyze! Stub libraries currently use YAML format, a fact that’s relevant when you try to interpret linker errors. If you’re curious about the format, read the tapi-tbdv4 man page. There’s also a JSON variant documented in the tapi-tbdv5 man page. Note Back in the day stub libraries used to be Mach-O files with all the code removed (MH_DYLIB_STUB). This format has long been deprecated in favour of TBD. Historically, the system maintained a dynamic linker shared cache, built at runtime from its working set of dynamic libraries. In macOS 11 and later this cache is included in the OS itself. Libraries in the cache are no longer present in their original locations on disk: % ls -lh /usr/lib/libSystem.B.dylib ls: /usr/lib/libSystem.B.dylib: No such file or directory Apple APIs, most notably dlopen, understand this and do the right thing if you supply the path of a library that moved into the cache. That’s true for some, but not all, command-line tools, for example: % dyld_info -exports /usr/lib/libSystem.B.dylib /usr/lib/libSystem.B.dylib [arm64e]: -exports: offset symbol … 0x5B827FE8 _mach_init_routine % nm /usr/lib/libSystem.B.dylib …/nm: error: /usr/lib/libSystem.B.dylib: No such file or directory When the linker creates a Mach-O image, it adds a bunch of helpful information to that image, including: The target platform The deployment target, that is, the minimum supported version of that platform Information about the tools used to build the image, most notably, the SDK version A build UUID For more information about the build UUID, see TN3178 Checking for and resolving build UUID problems. To dump the other information, run vtool. In some cases the OS uses the SDK version of the main executable to determine whether to enable new behaviour or retain old behaviour for compatibility purposes. You might see this referred to as compiled against SDK X. I typically refer to this as a linked-on-or-later check. Apple tools support the concept of autolinking. When your code uses a symbol from a module, the compiler inserts a reference (using the LC_LINKER_OPTION load command) to that module into the resulting object file (.o). When you link with that object file, the linker adds the referenced module to the list of modules that it searches when resolving symbols. Autolinking is obviously helpful but it can also cause problems, especially with cross-platform code. For information on how to enable and disable it, see the Build settings reference. Mach-O uses a two-level namespace. When a Mach-O image imports a symbol, it references the symbol name and the library where it expects to find that symbol. This improves both performance and reliability but it precludes certain techniques that might work on other platforms. For example, you can’t define a function called printf and expect it to ‘see’ calls from other dynamic libraries because those libraries import the version of printf from libSystem. To help folks who rely on techniques like this, macOS supports a flat namespace compatibility mode. This has numerous sharp edges — for an example, see the posts on this thread — and it’s best to avoid it where you can. If you’re enabling the flat namespace as part of a developer tool, search the ’net for dyld interpose to learn about an alternative technique. WARNING Dynamic linker interposing is not documented as API. While it’s a useful technique for developer tools, do not use it in products you ship to end users. Apple platforms use DWARF. When you compile a file, the compiler puts the debug info into the resulting object file. When you link a set of object files into a executable, dynamic library, or bundle for distribution, the linker does not include this debug info. Rather, debug info is stored in a separate debug symbols document package. This has the extension .dSYM and is created using dsymutil. Use symbols to learn about the symbols in a file. Use dwarfdump to get detailed information about DWARF debug info. Use atos to map an address to its corresponding symbol name. Different languages use different name mangling schemes: C, and all later languages, add a leading underscore (_) to distinguish their symbols from assembly language symbols. C++ uses a complex name mangling scheme. Use the c++filt tool to undo this mangling. Likewise, for Swift. Use swift demangle to undo this mangling. For a bunch more info about symbols in Mach-O, see Understanding Mach-O Symbols. This includes a discussion of weak references and weak definition. If your code is referencing a symbol unexpectedly, see Determining Why a Symbol is Referenced. To remove symbols from a Mach-O file, run strip. To hide symbols, run nmedit. It’s common for linkers to divide an object file into sections. You might find data in the data section and code in the text section (text is an old Unix term for code). Mach-O uses segments and sections. For example, there is a text segment (__TEXT) and within that various sections for code (__TEXT > __text), constant C strings (__TEXT > __cstring), and so on. Over the years there have been some really good talks about linking and libraries at WWDC, including: WWDC 2023 Session 10268 Meet mergeable libraries WWDC 2022 Session 110362 Link fast: Improve build and launch times WWDC 2022 Session 110370 Debug Swift debugging with LLDB WWDC 2021 Session 10211 Symbolication: Beyond the basics WWDC 2019 Session 416 Binary Frameworks in Swift — Despite the name, this covers XCFrameworks in depth. WWDC 2018 Session 415 Behind the Scenes of the Xcode Build Process WWDC 2017 Session 413 App Startup Time: Past, Present, and Future WWDC 2016 Session 406 Optimizing App Startup Time Note The older talks are no longer available from Apple, but you may be able to find transcripts out there on the ’net. Historically Apple published a document, Mac OS X ABI Mach-O File Format Reference, or some variant thereof, that acted as the definitive reference to the Mach-O file format. This document is no longer available from Apple. If you’re doing serious work with Mach-O, I recommend that you find an old copy. It’s definitely out of date, but there’s no better place to get a high-level introduction to the concepts. The Mach-O Wikipedia page has a link to an archived version of the document. For the most up-to-date information about Mach-O, see the declarations and doc comments in <mach-o/loader.h>. Revision History 2025-08-04 Added a link to Determining Why a Symbol is Referenced. 2025-06-29 Added information about autolinking. 2025-05-21 Added a note about the legacy Mach-O stub library format (MH_DYLIB_STUB). 2025-04-30 Added a specific reference to the man pages for the TBD format. 2025-03-01 Added a link to Understanding Mach-O Symbols. Added a link to TN3178 Checking for and resolving build UUID problems. Added a summary of the information available via vtool. Discussed linked-on-or-later checks. Explained how Mach-O uses segments and sections. Explained the old (-classic) and new (llvm-) tool variants. Referenced the Mach-O man page. Added basic info about the strip and nmedit tools. 2025-02-17 Expanded the discussion of dynamic library identification. 2024-10-07 Added some basic information about the dynamic linker shared cache. 2024-07-26 Clarified the description of the expected load address for Mach-O images. 2024-07-23 Added a discussion of position-independent images and the image slide. 2024-05-08 Added links to the demangling tools. 2024-04-30 Clarified the requirement to use the standard dynamic linker. 2024-03-02 Updated the discussion of static frameworks to account for Xcode 15 changes. Removed the link to WWDC 2018 Session 415 because it no longer works )-: 2024-03-01 Added the WWDC 2023 session to the list of sessions to make it easier to find. Added a reference to Using a Link Map to Track Down a Symbol’s Origin. Made other minor editorial changes. 2023-09-20 Added a link to Dynamic Library Identification. Updated the names for the static linker implementations (-ld_prime is no more!). Removed the beta epithet from Xcode 15. 2023-06-13 Defined the term Mach-O image. Added sections for both the static and dynamic linkers. Described the two big new features in Xcode 15: mergeable libraries and dependency verification. 2023-06-01 Add a reference to tapi-analyze. 2023-05-29 Added a discussion of the two-level namespace. 2023-04-27 Added a mention of the size tool. 2023-01-23 Explained the compile-time and run-time roles of a framework. Made other minor editorial changes. 2022-11-17 Added an explanation of TAPI. 2022-10-12 Added links to Mach-O documentation. 2022-09-29 Added info about .dSYM files. Added a few more links to WWDC sessions. 2022-09-21 First posted.
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Aug ’25
RECOLLECTING CODE FROM UPLOAD????
Hello All, I used to own an app named LOLIIPOP, and am in the process of transferring it to my new apple account. I am having two problems.... How do I transfer the source code and binary to my new apple account? My developers have an old code, so I need to send them the LAST code they uploaded to the App Store. How do I do that as well??? Please any help!!! Thanks, Mr. LM
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95
Aug ’25
lldb-dap closes connection
If I build an x64 binary on my M4 Mini, when I try to debug it using Visual Studio remote debugging the connection is closed, which means I cannot debug my code in x64 mode. I need to be able to do this as I have architecture specific code. I have Rosetta installed. FWIW I have the same issue with lldb-mi :( David
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Jul ’25
iOS AppPresser app logs out automatically after any period of time (Android works fine)
Hello, Thank you for taking the time to read this and hopefully helping me. https://apps.apple.com/gb/app/gdl-graded-darts-leagues/id1592502150 I created a mobile app using AppPresser that is connected to my WordPress website. The iOS app is logging users out when they close the app and go back to it. The login session does not persist, and users are forced to log in again frequently. This happens at any time period between closing and opening the app. This only happens on iOS — Android keeps the session active as expected. I don't know if I've included this post in the correct topic, sorry. Thanks again for any ideas and assistance!
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Jul ’25
React native app crash on TestFlight
Good day everyone. I have a react native app which works on dev mode on my device - Iphone 13 pro version: 18.5, but when deployed to TestFlight and installed on same device it crashes when ever I click on any TextInput. I downloaded the crash file but finding it difficult to pinpoint the problem. I want to know what the problem is, if it's related to an installed package or code base or any other. Any help will be appreciated!!! Thanks. crashlog.crash
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Jul ’25
Using alternate app icons with Icon Composer
I've been messing around with converting my app icons to use Icon Composer. My app has multiple app icons, but I've noticed that I cant seem to set .icon files using the alternate app icon api. I believe this is due to the requirement that alternate app icons live in the Assets Catalogue but .icon files go anywhere in your project. Is there any plan to support this? Or am i missing something? I was able to successfully set a .icon file for the primary app icon.
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Jul ’25
Assets.car not being built as part of the archiving and distribution process
I am working on a MAUI application. When I go to archive my build to then release it, my bundle is not including the Assets.car file that apple is seemingly expecting for handling the app icons, which is leading to issues trying to publish my app. The assets are in a AppIcon.appiconset folder in my project (under Platforms>iOS>Resources) with a proper Contents.json file also in there. They are setup as a BundledResource (also have tried ImageAssets for the build type but with the same issue occurring). I am using visual studio 2022 on Windows 11 paired with a Mac (Sequoia 15.5) and Xcode 16.4. I have even tried manually compiling the asset catalog from xcode16.4 and trying to use terminal commands to have actool create the Assets.car but that runs with no files created to the output destination as well as no errors. I believe there may be an issue with actools in my Xcode copy. I have tried uninstalling and reinstalling with no luck. Any suggestions or tips?
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Jul ’25
Best replacement for MCL
So, as we found out from WWDC, the migration to Apple Silicon is inevitable. Does anyone have a good recommendation for a replacement for Macintosh Common Lisp on Apple Silicon? I was using it back in the MPW days and struggling to keep the Lisp code working, but Apple Silicon has thrown a money wrench at it! Thanks in advance for any advice on any available Apple Silicon Lisp development tools!
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Jul ’25
The bundle does not contain an app icon for iPhone / iPod Touch of exactly '120x120' pixels
Trying to publish my .NET MAUI app via the transporter after migrating it from Xamarin (using the App Store Connect feature directly within visual studio 2022 has never worked for me) and getting this error. Validation failed (409) Missing required icon file. The bundle does not contain an app icon for iPhone / iPod Touch of exactly '120x120' pixels, in .png format for iOS versions >= 10.0. To support older versions of iOS, the icon may be required in the bundle outside of an asset catalog. Make sure the Info.plist file includes appropriate entries referencing the file. I have setup my maui app to use the asset catalog with the .pngs setup as bundled resources and I have also tried using the .svg method, both resulting in this error. When I zip and unzip my .ipa file I can see the asset catalog as part of the payload (C:\Archives\AIM_MAUI\Payload\AIM_MAUI.app\AppIcon.appiconset) Here is the contents of the Contents.json file { "images" : [ { "filename" : "icon_40.png", "idiom" : "iphone", "scale" : "2x", "size" : "20x20" }, { "filename" : "icon_60.png", "idiom" : "iphone", "scale" : "3x", "size" : "20x20" }, { "filename" : "icon_58.png", "idiom" : "iphone", "scale" : "2x", "size" : "29x29" }, { "filename" : "icon_87.png", "idiom" : "iphone", "scale" : "3x", "size" : "29x29" }, { "filename" : "icon_80.png", "idiom" : "iphone", "scale" : "2x", "size" : "40x40" }, { "filename" : "icon_120.png", "idiom" : "iphone", "scale" : "3x", "size" : "40x40" }, { "filename" : "icon_120.png", "idiom" : "iphone", "scale" : "2x", "size" : "60x60" }, { "filename" : "icon_180.png", "idiom" : "iphone", "scale" : "3x", "size" : "60x60" }, { "filename" : "icon_20.png", "idiom" : "ipad", "scale" : "1x", "size" : "20x20" }, { "filename" : "icon_40.png", "idiom" : "ipad", "scale" : "2x", "size" : "20x20" }, { "filename" : "icon_29.png", "idiom" : "ipad", "scale" : "1x", "size" : "29x29" }, { "filename" : "icon_58.png", "idiom" : "ipad", "scale" : "2x", "size" : "29x29" }, { "filename" : "icon_40.png", "idiom" : "ipad", "scale" : "1x", "size" : "40x40" }, { "filename" : "icon_80.png", "idiom" : "ipad", "scale" : "2x", "size" : "40x40" }, { "filename" : "icon_76.png", "idiom" : "ipad", "scale" : "1x", "size" : "76x76" }, { "filename" : "icon_152.png", "idiom" : "ipad", "scale" : "2x", "size" : "76x76" }, { "filename" : "icon_167.png", "idiom" : "ipad", "scale" : "2x", "size" : "83.5x83.5" }, { "filename" : "icon_1024.png", "idiom" : "ios-marketing", "scale" : "1x", "size" : "1024x1024" } ], "info" : { "author" : "xcode", "version" : 1 } } I have tried manually using the actool tool from Xcode 16.4 to create the Assets.car file that is seeming to be missing and leading to this issue but even that can't compile the icons (or even a simple sample appicon.appiconset from Xcode with a singular .png added) and I am beginning to think there's an issue with the actool itself. I have tried reinstalling Xcode and every time the actool is just a partial download or a stub of the tool and not the real tool (actool size on my Mac is only 170kb and per my research it should be at least a couple mb) Is there any workaround?
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276
Jul ’25
Gyro/Orientation iframe embed doesn't work on iOS26, works on iOS 18.5
So I'm testing a microapp that is contained in an IPFS folder. I use a web3 website that is used to view NFTs and their IPFS files. The app has gyro controls, which are enabled through a confirmation gesture. In iOS 18.5, when I press "Request Permission" button I get the popup to allow the app to acess movement and orientation. In iOS26, pressing the button does nothing. Keep in mind that this only happens through the website, that uses iframes. When I load the IPFS file from a direct link, the popup appears with no issue. I think this might be because iOS26 uses WebGPU or it might be a bug since iOS26 is still in beta.
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Jul ’25
Determining Why a Symbol is Referenced
Recently a bunch of folks have asked about why a specific symbol is being referenced by their app. This is my attempt to address that question. If you have questions or comments, please start a new thread. Tag it with Linker so that I see it. Share and Enjoy — Quinn “The Eskimo!” @ Developer Technical Support @ Apple let myEmail = "eskimo" + "1" + "@" + "apple.com" Determining Why a Symbol is Referenced In some situations you might want to know why a symbol is referenced by your app. For example: You might be working with a security auditing tool that flags uses of malloc. You might be creating a privacy manifest and want to track down where your app is calling stat. This post is my attempt at explaining a general process for tracking down the origin of these symbol references. This process works from ‘below’. That is, it works ‘up’ from you app’s binary rather than ‘down’ from your app’s source code. That’s important because: It might be hard to track down all of your source code, especially if you’re using one or more package management systems. If your app has a binary dependency on a static library, dynamic library, or framework, you might not have access to that library’s source code. IMPORTANT This post assumes the terminology from An Apple Library Primer. Read that before continuing here. The general outline of this process is: Find all Mach-O images. Find the Mach-O image that references the symbol. Find the object files (.o) used to make that Mach-O. Find the object file that references the symbol. Find the code within that object file. Those last few steps require some gnarly low-level Mach-O knowledge. If you’re looking for an easier path, try using the approach described in the A higher-level alternative section as a replacement for steps 3 through 5. This post assumes that you’re using Xcode. If you’re using third-party tools that are based on Apple tools, and specifically Apple’s linker, you should be able to adapt this process to your tooling. If you’re using a third-party tool that has its own linker, you’ll need to ask for help via your tool’s support channel. Find all Mach-O images On Apple platforms an app consists of a number of Mach-O images. Every app has a main executable. The app may also embed dynamic libraries or frameworks. The app may also embed app extensions or system extensions, each of which have their own executable. And a Mac app might have embedded bundles, helper tools, XPC services, agents, daemons, and so on. To find all the Mach-O images in your app, combine the find and file tools. For example: % find "Apple Configurator.app" -print0 | xargs -0 file | grep Mach-O Apple Configurator.app/Contents/MacOS/Apple Configurator: Mach-O universal binary with 2 architectures: [x86_64:Mach-O 64-bit executable x86_64] [arm64] … Apple Configurator.app/Contents/MacOS/cfgutil: Mach-O universal binary with 2 architectures: [x86_64:Mach-O 64-bit executable x86_64] [arm64:Mach-O 64-bit executable arm64] … Apple Configurator.app/Contents/Extensions/ConfiguratorIntents.appex/Contents/MacOS/ConfiguratorIntents: Mach-O universal binary with 2 architectures: [x86_64:Mach-O 64-bit executable x86_64] [arm64:Mach-O 64-bit executable arm64] … Apple Configurator.app/Contents/Frameworks/ConfigurationUtilityKit.framework/Versions/A/ConfigurationUtilityKit: Mach-O universal binary with 2 architectures: [x86_64:Mach-O 64-bit dynamically linked shared library x86_64] [arm64] … This shows that Apple Configurator has a main executable (Apple Configurator), a helper tool (cfgutil), an app extension (ConfiguratorIntents), a framework (ConfigurationUtilityKit), and many more. This output is quite unwieldy. For nicer output, create and use a shell script like this: % cat FindMachO.sh #! /bin/sh # Passing `-0` to `find` causes it to emit a NUL delimited after the # file name and the `:`. Sadly, macOS `cut` doesn’t support a nul # delimiter so we use `tr` to convert that to a DLE (0x01) and `cut` on # that. # # Weirdly, `find` only inserts the NUL on the primary line, not the # per-architecture Mach-O lines. We use that to our advantage, filtering # out the per-architecture noise by only passing through lines # containing a DLE. find "$@" -type f -print0 \ | xargs -0 file -0 \ | grep -a Mach-O \ | tr '\0' '\1' \ | grep -a $(printf '\1') \ | cut -d $(printf '\1') -f 1 Find the Mach-O image that references the symbol Once you have a list of Mach-O images, use nm to find the one that references the symbol. The rest of this post investigate a test app, WaffleVarnishORama, that’s written in Swift but uses waffle management functionality from the libWaffleCore.a static library. The goal is to find the code that calls calloc. This app has a single Mach-O image: % FindMachO.sh "WaffleVarnishORama.app" WaffleVarnishORama.app/WaffleVarnishORama Use nm to confirm that it references calloc: % nm "WaffleVarnishORama.app/WaffleVarnishORama" | grep "calloc" U _calloc The _calloc symbol has a leading underscore because it’s a C symbol. This convention dates from the dawn of Unix, where the underscore distinguish C symbols from assembly language symbols. The U prefix indicates that the symbol is undefined, that is, the Mach-O images is importing the symbol. If the symbol name is prefixed by a hex number and some other character, like T or t, that means that the library includes an implementation of calloc. That’s weird, but certainly possible. OTOH, if you see this then you know this Mach-O image isn’t importing calloc. IMPORTANT If this Mach-O isn’t something that you build — that is, you get this Mach-O image as a binary from another developer — you won’t be able to follow the rest of this process. Instead, ask for help via that library’s support channel. Find the object files used to make that Mach-O image The next step is to track down which .o file includes the reference to calloc. Do this by generating a link map. A link map is an old school linker feature that records the location, size, and origin of every symbol added to the linker’s output. To generate a link map, enable the Write Link Map File build setting. By default this puts the link map into a text (.txt) file within the derived data directory. To find the exact path, look at the Link step in the build log. If you want to customise this, use the Path to Link Map File build setting. A link map has three parts: A simple header A list of object files used to build the Mach-O image A list of sections and their symbols In our case the link map looks like this: # Path: …/WaffleVarnishORama.app/WaffleVarnishORama # Arch: arm64 # Object files: [ 0] linker synthesized [ 1] objc-file [ 2] …/AppDelegate.o [ 3] …/MainViewController.o [ 4] …/libWaffleCore.a[2](WaffleCore.o) [ 5] …/Foundation.framework/Foundation.tbd … # Sections: # Address Size Segment Section 0x100008000 0x00001AB8 __TEXT __text … The list of object files contains: An object file for each of our app’s source files — That’s AppDelegate.o and MainViewController.o in this example. A list of static libraries — Here that’s just libWaffleCore.a. A list of dynamic libraries — These might be stub libraries (.tbd), dynamic libraries (.dylib), or frameworks (.framework). Focus on the object files and static libraries. The list of dynamic libraries is irrelevant because each of those is its own Mach-O image. Find the object file that references the symbol Once you have list of object files and static libraries, use nm to each one for the calloc symbol: % nm "…/AppDelegate.o" | grep calloc % nm "…/MainViewController.o" | grep calloc % nm "…/libWaffleCore.a" | grep calloc U _calloc This indicates that only libWaffleCore.a references the calloc symbol, so let’s focus on that. Note As in the Mach-O case, the U prefix indicates that the symbol is undefined, that is, the object file is importing the symbol. Find the code within that object file To find the code within the object file that references the symbol, use the objdump tool. That tool takes an object file as input, but in this example we have a static library. That’s an archive containing one or more object files. So, the first step is to unpack that archive: % mkdir "libWaffleCore-objects" % cd "libWaffleCore-objects" % ar -x "…/libWaffleCore.a" % ls -lh total 24 -rw-r--r-- 1 quinn staff 4.1K 8 May 11:24 WaffleCore.o -rw-r--r-- 1 quinn staff 56B 8 May 11:24 __.SYMDEF SORTED There’s only a single object file in that library, which makes things easy. If there were a multiple, run the following process over each one independently. To find the code that references a symbol, run objdump with the -S and -r options: % xcrun objdump -S -r "WaffleCore.o" … ; extern WaffleRef newWaffle(void) { 0: d10083ff sub sp, sp, #32 4: a9017bfd stp x29, x30, [sp, #16] 8: 910043fd add x29, sp, #16 c: d2800020 mov x0, #1 10: d2800081 mov x1, #4 ; Waffle * result = calloc(1, sizeof(Waffle)); 14: 94000000 bl 0x14 <ltmp0+0x14> 0000000000000014: ARM64_RELOC_BRANCH26 _calloc … Note the ARM64_RELOC_BRANCH26 line. This tells you that the instruction before that — the bl at offset 0x14 — references the _calloc symbol. IMPORTANT The ARM64_RELOC_BRANCH26 relocation is specific to the bl instruction in 64-bit Arm code. You’ll see other relocations for other instructions. And the Intel architecture has a whole different set of relocations. So, when searching this output don’t look for ARM64_RELOC_BRANCH26 specifically, but rather any relocation that references _calloc. In this case we’ve built the object file from source code, so WaffleCore.o contains debug symbols. That allows objdump include information about the source code context. From that, we can easily see that calloc is referenced by our newWaffle function. To see what happens when you don’t have debug symbols, create an new object file with them stripped out: % cp "WaffleCore.o" "WaffleCore-stripped.o" % strip -x -S "WaffleCore-stripped.o" Then repeat the objdump command: % xcrun objdump -S -r "WaffleCore-stripped.o" … 0000000000000000 <_newWaffle>: 0: d10083ff sub sp, sp, #32 4: a9017bfd stp x29, x30, [sp, #16] 8: 910043fd add x29, sp, #16 c: d2800020 mov x0, #1 10: d2800081 mov x1, #4 14: 94000000 bl 0x14 <_newWaffle+0x14> 0000000000000014: ARM64_RELOC_BRANCH26 _calloc … While this isn’t as nice as the previous output, you can still see that newWaffle is calling calloc. A higher-level alternative Grovelling through Mach-O object files is quite tricky. Fortunately there’s an easier approach: Use the -why_live option to ask the linker why it included a reference to the symbol. To continue the above example, I set the Other Linker Flags build setting to -Xlinker / -why_live / -Xlinker / _calloc and this is what I saw in the build transcript: _calloc from /usr/lib/system/libsystem_malloc.dylib _newWaffle from …/libWaffleCore.a[2](WaffleCore.o) _$s18WaffleVarnishORama18MainViewControllerC05tableE0_14didSelectRowAtySo07UITableE0C_10Foundation9IndexPathVtFTf4dnn_n from …/MainViewController.o _$s18WaffleVarnishORama18MainViewControllerC05tableE0_14didSelectRowAtySo07UITableE0C_10Foundation9IndexPathVtF from …/MainViewController.o Demangling reveals a call chain like this: calloc newWaffle WaffleVarnishORama.MainViewController.tableView(_:didSelectRowAt:) WaffleVarnishORama.MainViewController.tableView(_:didSelectRowAt:) and that should be enough to kick start your investigation. IMPORTANT The -why_live option only works if you dead strip your Mach-O image. This is the default for the Release build configuration, so use that for this test. Revision History 2025-07-18 Added the A higher-level alternative section. 2024-05-08 First posted.
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Information about legacy (new app)
Hello I developed an app for my cousin (I wrote all the code myself), but she’ll be the one managing it once it’s published. She’ll take care of the content, updates, and anything admin-related. Right now, the app uses my Firebase account and my Apple Developer account (App Store Connect), which I set up at the start of the project. I’m wondering: • Am I at risk legally or financially if the accounts stay under my name, even though I won’t be involved in the app after release? • Is it possible to migrate the project to her email, meaning transfer Firebase and the Apple Developer account to her own account, so that everything is properly under her control? Thanks in advance for any insights or experiences
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Jul ’25
The signature of cannot be validated and may have been compromised
I'm currently developing a Unity game for iPad and have run into a critical issue that's completely blocking me from building the project. The project uses the Mapbox SDK for Unity. Everything was working fine during today test build on the iPad. I made minor changes - just four scripts, then attempted another build. However, Xcode began showing the following error: The signature of “MapboxCommon.xcframework” cannot be validated and may have been compromised. Validation Error: The signing certificate has been revoked (CSSMERR_TP_CERT_REVOKED) This error now occurs consistently. I've tried building on a different MacBook and with a different Apple account, but the result is the same. I haven't made any changes to the Mapbox framework, nor have I updated it recently. I'm trying to determine the root cause: Is this something I've done on my end? Or is it an issue with the Mapbox framework or their signing certificate? Is there a temporary workaround that would allow me to proceed with development builds while I investigate a proper fix? Any insights or suggestions would be greatly appreciated.
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Jul ’25
Unable to Add Font to Asset Catalog as a Font Set (Appearing as "Data")
Hi Support Team, I am new here. I am unable to add my fonts to the asset catalog there is no option to add new font set when I click the plus sign. When I drag my files in they show up as data. I have a Contents.json in the font folder called BeVietnamProFont.font. Is there something I am doing wrong? Thanks SO much! { "info": { "version": 1, "author": "xcode" }, "properties": {}, "fonts": [ { "filename": "BeVietnamPro-Black.ttf", "weight": "black", "style": "normal" }, { "filename": "BeVietnamPro-BlackItalic.ttf", "weight": "black", "style": "italic" }, { "filename": "BeVietnamPro-Bold.ttf", "weight": "bold", "style": "normal" }, { "filename": "BeVietnamPro-BoldItalic.ttf", "weight": "bold", "style": "italic" }, { "filename": "BeVietnamPro-ExtraBold.ttf", "weight": "heavy", "style": "normal" }, { "filename": "BeVietnamPro-ExtraBoldItalic.ttf", "weight": "heavy", "style": "italic" }, { "filename": "BeVietnamPro-ExtraLight.ttf", "weight": "ultralight", "style": "normal" }, { "filename": "BeVietnamPro-ExtraLightItalic.ttf", "weight": "ultralight", "style": "italic" }, { "filename": "BeVietnamPro-Light.ttf", "weight": "light", "style": "normal" }, { "filename": "BeVietnamPro-LightItalic.ttf", "weight": "light", "style": "italic" }, { "filename": "BeVietnamPro-Regular.ttf", "weight": "regular", "style": "normal" }, { "filename": "BeVietnamPro-Italic.ttf", "weight": "regular", "style": "italic" }, { "filename": "BeVietnamPro-Medium.ttf", "weight": "medium", "style": "normal" }, { "filename": "BeVietnamPro-MediumItalic.ttf", "weight": "medium", "style": "italic" }, { "filename": "BeVietnamPro-SemiBold.ttf", "weight": "semibold", "style": "normal" }, { "filename": "BeVietnamPro-SemiBoldItalic.ttf", "weight": "semibold", "style": "italic" }, { "filename": "BeVietnamPro-Thin.ttf", "weight": "thin", "style": "normal" }, { "filename": "BeVietnamPro-ThinItalic.ttf", "weight": "thin", "style": "italic" } ] } ![]("https://developer.apple.com/forums/content/attachment/56835f04-d1c1-468f-808b-9a786562d367" "title=Screenshot 2025-07-13 at 1.05.05 PM.png ;width=539;height=630")
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Jul ’25
"Show API Changes" no longer available on Apple Developer Documentation website?
There was a time that Apple Developer Documentation provides a filter to show the changes across versions, at https://developer.apple.com/documentation/technologies , with purple (modified), green (added), and red (deprecated) annotations. I wonder if this feature is completely removed, or is it still hiding somewhere? It is helpful to diff the API changes among versions. Thanks. edit: as pointed out by Rick, here is an archive link to what it used to look like
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