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SwiftMacros Not able to access of main project XCTest File.
I have developed a Swift macro called @CodableInit in the SwiftCodableMacro module, and I’m able to use it successfully in my main project. Here’s an example usage: import SwiftCodableMacro @CodableInit // This is for Codable macros public class ErrorMonitoringWebPlugin { public var identifier: UUID = UUID() // MARK: - Codable required public init(from decoder:Decoder) throws { let values = try decoder.container(keyedBy: CodingKeys.self) identifier = try values.decode(UUID.self, forKey: .identifier) } } However, when I try to write a unit test for the ErrorMonitoringWebPlugin class, I encounter an issue. Here's the test case: func testCodableSubjectIdentifierShouldEqualDecodedSubjectIdentifier() { self.measure { let encoder = JSONEncoder() let data = try? encoder.encode(subject) //Here I am getting this error Class 'JSONEncoder' requires that 'ErrorMonitoringWebPlugin' conform to 'Encodable' let decoder = JSONDecoder() let decodedSubject = try? decoder.decode(ErrorMonitoringWebPlugin.self, from: data!) XCTAssertEqual(subject.identifier, decodedSubject?.identifier) } } The compiler throws an error saying: Class 'JSONEncoder' requires that 'ErrorMonitoringWebPlugin' conform to 'Encodable' Even though the @CodableInit macro is supposed to generate conformance, it seems that this macro-generated code is not visible or active inside the test target. How can I ensure that the @CodableInit macro (from SwiftCodableMacro) is correctly applied and recognized within the XCTest target of my main project?
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58
Jun ’25
iOS App'te Elektronik Sözleşme Onayı ve Hukuki Geçerlilik Süreci (KVKK - SwiftUI)
Merhaba, iOS üzerinde bir sözleşme onay uygulaması geliştiriyorum. Kullanıcıların dijital ortamda sözleşmeleri okuyup onaylaması gerekiyor. Ancak hukuki geçerlilik konusunda bazı tereddütlerim vardı. Bursa’da yaşayan biri olarak bu konuda bir avukata danışmam gerekti. Şans eseri https://www.avukatcanata.com ile karşılaştım ve hem bireysel hem ticari sözleşmeler konusunda gerçekten çok net açıklamalar sundular. Özellikle elektronik imza ve KVKK uyumu hakkında verdikleri bilgiler sayesinde projemi yasal zemine oturtabildim. Eğer bu tarz uygulamalar geliştiriyorsanız, mutlaka bir hukukçu görüşü alın. Yanlış bir adım size veya kullanıcınıza ciddi sonuçlar doğurabilir. Teşekkürler 🍏
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Jul ’25
Public radar reports
Hello Apple community ! Not here to report an issue but I just wanted to make a suggestion ^^ I feel like a common frustration amongst developers is the lack of transparency over bugs filed on developer tools, SDKs, iOS versions, the whole Apple ecosystem really. This leads to the creation of parallel bug tracking tools (https://github.com/feedback-assistant/reports?tab=readme-ov-file / https://openradar.appspot.com/page/1) or filing of duplicates for reports that may already exist and are being worked on. I feel like this would save time for both external developers that encounter bugs & Apple engineers that have to look for possible duplicates to share a common public database of issues. Other companies have this kind of system in place (Google for example : https://issuetracker.google.com/) so why not Apple ? Thank you
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May ’25
Issue with Custom Error Message on invalidate in CoreNFC APDU Tag Reader Session
Hi everyone, I'm working on an NFC-related app using CoreNFC with APDU commands to read and write tags. I’ve encountered an issue when trying to handle the scenario where the user cancels the NFC session. Here’s what’s happening: When a user cancels the NFC session manually (e.g., by tapping "Cancel"), I see an error log indicating tagReaderSession|userCancelled. However, when I explicitly call session.invalidate(errorMessage: "No NFC tag found") in my code to handle a scenario where no tag is detected, the session still shows the error as userCancelled instead of my custom error message. This behavior is confusing both in terms of debugging and for providing feedback to users, as I expect my custom message to appear instead of the generic "user cancelled" message. func tagReaderSessionDidBecomeActive(_ session: NFCTagReaderSession) { // Session becomes active } func tagReaderSession(_ session: NFCTagReaderSession, didDetect tags: [NFCTag]) { // Handle tag detection logic } func tagReaderSession(_ session: NFCTagReaderSession, didInvalidateWithError error: Error) { print("Session invalidated with error: \(error.localizedDescription)") } func handleNoTagDetected(session: NFCTagReaderSession) { session.invalidate(errorMessage: "No NFC tag found") } I call handleNoTagDetected(session:) explicitly when no tag is detected, expecting the custom error message to show. However, the system still shows the cancellation error. Has anyone else experienced this behavior? Is this the intended behavior for CoreNFC, or am I missing something in my implementation? Any guidance would be appreciated. Thanks in advance!
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Jan ’25
"Trust This Computer?" glitch
Hello everyone, my iPhone keep on showing multiple "Trust this Computer" alert simultaneously which I cannot tap on it to Trust. As a result, I cannot run my XCode project on my device. Does anyone has any ideas or solutions to fix this ? Solution I have tried: Reset Location & Privacy Reset Network Settings Enable Developer Mode Restart Device My devices specs: iPhone 15 Pro: iOS 18.2.1 Macbook Pro M3 Max: Sequoia 15.1.1
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Jan ’25
Investigating Third-Party IDE Integration Problems
I regularly see questions from folks who’ve run into problems with their third-party IDE on macOS. Specifically, the issue is that their IDE is invoking Apple’s command-line tools — things like clang and ld — and that’s failing in some way. This post collects my ideas on how to investigate, and potentially resolve, issues like this. If you have any questions or comments, please put them in a new thread here on DevForums. Tag it appropriately so that I see it. Good tags include Compiler, Linker, LLVM, and Command Line Tools. Share and Enjoy — Quinn “The Eskimo!” @ Developer Technical Support @ Apple let myEmail = "eskimo" + "1" + "@" + "apple.com" Investigating Third-Party IDE Integration Problems Many third-party IDEs rely on Apple tools. For example, the IDE might run clang to compile C code or run ld to link object files. These IDEs typically don’t include the tools themselves. Rather, they rely on you to install Xcode or Apple’s Command Line Tools package. These are available at Apple > Developer > Downloads Occasionally I see folks having problems with this. They most typically report that basic stuff, like compiling a simple C program, fails with some mysterious error. If you’re having such a problem, follow the steps below to investigate it. IMPORTANT Some IDEs come with their own tools for compiling and linking. Such IDEs are not the focus of this post. If you have problems with an IDE like that, contact its vendor. Select Your Tools macOS has a concept of the current command-line tools. This can either point to the tools within Xcode or to an installed Command Line Tools package. To see which tools are currently selected, run xcode-select with the --print-path argument. This is what you’ll see if you have Xcode installed in the Applications folder: % xcode-select --print-path /Applications/Xcode.app/Contents/Developer Note All of the tools I discuss here are documented in man pages. If you’re not familiar with those, see Reading UNIX Manual Pages. And this is what you’ll see with a Command Line Tools package selected. % xcode-select --print-path /Library/Developer/CommandLineTools There are two common problems with this: It points to something you’ve deleted. It points to something unexpected. Run the command above to see the current state. If necessary, change the state using the --switch option. For example: % xcode-select --print-path /Applications/Xcode.app/Contents/Developer % clang -v Apple clang version 14.0.3 (clang-1403.0.22.14.1) … % sudo xcode-select --switch ~/XcodeZone/Xcode-beta.app % clang -v Apple clang version 15.0.0 (clang-1500.0.38.1) … I have Xcode 14.3 in the Applications folder and thus clang runs Clang 14.0.3. I have Xcode 15.0b5 in ~/XcodeZone, so switching to that yields Clang 15.0.0. It’s possible to run one specific command with different tools. See Select Your Tools Temporarily, below. Run a Simple Test A good diagnostic test is to use the selected command-line tools to compile a trivial test program. Consider this C [1] example: % cat hello.c #include <stdio.h> int main(int argc, char ** argv) { printf("Hello Cruel World!\n"); return 0; } % clang -o hello hello.c % ./hello Hello Cruel World! IMPORTANT If possible, run this from Terminal rather than, say, over SSH. You may need to expand this test program to exercise your specific case. For example, if your program is hitting an error when it tries to import the Core Foundation framework, add that import to your test program: % cat hello.c #include <stdio.h> #include <CoreFoundation/CoreFoundation.h> int main(int argc, char ** argv) { printf("Hello Cruel World!\n"); return 0; } When you compile your test program, you might see one of these results: Your test program compiles. Your test program fails with a similar error. Your test program fails with a different error. I’ll explore each case in turn. [1] For a C++ example, see C++ Issues, below. If your test program compiles… If your test program compiles from the shell, that proves that your basic command-line tools setup is fine. If the same program fails to compile in your IDE, there’s something IDE-specific going on here. I can’t help you with that. I recommend that you escalate the issue via the support channel for your IDE. If your test program fails with a similar error… If your test program fails with an error similar to the one you’re seeing in your IDE, there are two possibilities: There’s a bug in your test program’s code. There’s an environmental issue that’s affecting your command-line tools setup. Don’t rule out the first possibility. I regularly see folks bump into problems like this, where it turns out to be a bug in their code. For a specific example, see C++ Issues, below. Assuming, however, that your test program’s code is OK, it’s time to investigate environmental issues. See Vary Your Environment, below. If your test program fails with a different error… If your test program fails with a different error, look at the test program’s code to confirm that it’s correct, and that it accurately reflects the code you’re trying to run in your IDE. Vary Your Environment If your test program fails with the same error as you’re seeing in your IDE, and you are sure that the code is correct, it’s time to look for environmental factors. I typically do this with the steps described in the next sections, which are listed from most to least complex. These steps only tell you where things are going wrong, not what is going wrong. However, that’s often enough to continue the investigation of your issue. Vary Your Shell Try running your commands in a different shell. macOS’s default shell is zsh. Try running your commands in bash instead: % bash … bash-3.2$ clang -o hello hello.c bash-3.2$ ./hello Hello Cruel World! Or if you’ve switched your shell to bash, try it in zsh. Vary Your User Account Some problems are caused by settings tied to your user account. To investigate whether that’s an issue here: Use System Settings > Users & Groups to create a new user. Log in as that user. Run your test again. Vary Your Mac Some problems are system wide, so you need to test on a different Mac. The easiest way to do that is to set up a virtual machine (VM) and run your test there. Or, if you have a separate physical Mac, run your test on that. Vary Your Site If you’re working for an organisation, they may have installed software on your Mac that causes problems. If you have a Mac at home, try running your test there. It’s also possible that your network is causing problems [1]. If you have a laptop, try taking it to a different location to see if that changes things. [1] I rarely see this when building a simple test program, but it do see it with other stuff, like code signing. C++ Issues If you’re using C++, here’s a simple test you can try: % cat hello.cpp #include <iostream> int main() { std::cout << "Hello Cruel World!\n"; } % clang++ -o hello hello.cpp % ./hello Hello Cruel World! A classic problem with C++ relates to name mangling. Consider this example: % cat hello.c #include <stdio.h> #include "hello-core.h" int main(int argc, char ** argv) { HCSayHello(); return 0; } % cat hello-core.cpp #include "hello-core.h" #include <iostream> extern void HCSayHello() { std::cout << "Hello Cruel World!\n"; } % cat hello-core.h extern void HCSayHello(); % clang -c hello.c % clang++ -c hello-core.cpp % clang++ -o hello hello.o hello-core.o Undefined symbols for architecture x86_64: "_HCSayHello", referenced from: _main in hello.o ld: symbol(s) not found for architecture x86_64 clang: error: linker command failed with exit code 1 (use -v to see invocation) The issue here is that C++ generates a mangled name for HCSayHello: % nm hello-core.o | grep HCSayHello 0000000000000000 T __Z10HCSayHellov whereas C uses the non-mangled name: % nm hello.o | grep HCSayHello U _HCSayHello The fix is an appropriate application of extern "C": % cat hello-core.h extern "C" { extern void HCSayHello(); }; Select Your Tools Temporarily Sometimes you want to temporarily run a command from a particular tools package. To continue my earlier example, I currently have Xcode 14.3 installed in the Applications folder and Xcode 15.0b5 in ~/XcodeZone. Xcode 14.3 is the default but I can override that with the DEVELOPER_DIR environment variable: % clang -v Apple clang version 14.0.3 (clang-1403.0.22.14.1) … % DEVELOPER_DIR=~/XcodeZone/Xcode-beta.app/Contents/Developer clang -v Apple clang version 15.0.0 (clang-1500.0.38.1) … Revision History 2025-01-27 Remove the full width characters. These were a workaround for a forums platform bug that’s since been fixed. Made other minor editorial changes. 2023-07-31 First posted.
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1.8k
Jan ’25
Help Analyzing Crash Logs – Auto Layout Threading Violation, Memory Pressure, CPU Usage
We're facing critical stability issues with a Xamarin-based iOS warehouse management app and need expert validation of our crash log analysis. We’re seeing recurring issues related to: Auto Layout Threading Violations Memory Pressure Terminations CPU Resource Usage Violations These are causing app crashes and performance degradation in production. We've attached representative crash logs to this post. Technical Validation Questions: Do the crash logs point to app-level defects (e.g., threading/memory management), or could user behavior be a contributing factor? Is ~1.8GB memory usage acceptable for enterprise apps on iOS, or does it breach platform best practices? Do the threading violations suggest a fundamental architectural or concurrency design flaw in the codebase? Would you classify these as enterprise-grade stability concerns requiring immediate architectural refactoring? Do the memory logs indicate potential leaks, or are the spikes consistent with expected usage patterns under load? Could resolving the threading violation eliminate or reduce the memory and CPU issues (i.e., a cascading failure)? Are these issues rooted in Xamarin framework limitations, or do they point more toward app-specific implementation problems? Documentation & UX Questions: What Apple-recommended solutions exist for these specific issues? (e.g., memory management, thread safety, layout handling) From your experience, how would these issues manifest for users? (e.g., crashes, slow performance, logout events, unresponsive UI, etc. JetsamEvent-2025-05-27-123434_REDACTED.ips ) WarehouseApp.iOS.cpu_resource-2025-05-30-142737_REDACTED.ips WarehouseApp.iOS-2025-05-27-105134_REDACTED.ips Any insights, analysis, or references would be incredibly helpful. Thanks in advance!
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69
Jun ’25
"No Such Module" When Using Mergable Libraries In a Static XCFramework
I'm attempting to create a proof of concept of a static library, distributed as an XCFramework, which has two local XCFramework dependencies. The reason for this is because I'm working to provide a single statically linked library to a customer, instead of providing them with the static library plus the two dependencies. The Issue With a fairly simple example project, I'm not able to access any code from the static library without the complier throwing a "No such module" error and saying that it cannot find one of the dependent modules. Project Layout I have an example project that has some example targets with basic example code. Example Project on Github Target: FrameworkA Mach-0 Type: Dynamic Build Mergable Library: Yes Skip Install: No Build Libraries For Distribution: Yes Target: FrameworkB Mach-0 Type: Dynamic Build Mergable Library: Yes Skip Install: No Build Libraries For Distribution: Yes XCFrameworks are being generated from these two targets using Apple's recommendations. I've verified that the mergable metadata is present in both framework's Info.plist files. Each exposes a single struct which will return an example String. Finally I have my SDK target: Target: ExampleKit Mach-0 Type: Static Build Mergable Library: No Create Merged Binary: Manual Skip Install: No Build Libraries For Distribution: Yes The two .xcframework files are in the Target's folder structure as well. The "Link Binary With Libraries" build phase includes them and they're Required. Inside of the ExampleKit target, I have a single public struct which has two static properties which return the example strings from FrameworkA and FrameworkB. I then have another script which generates an XCFramework from this target. Expectations Based on Apple's documentation and the "Meet Mergable Libraries" WWDC session I would expect that I could make a simple iOS app, link the ExampleKit.xcframework, import ExampleKit inside of a file, and be able to access the single public struct present in ExampleKit. Unfortunately, all I get is "No such module FrameworkA". I would expect that FrameworkA and FrameworkB would have been merged into ExampleKit? I'm really unsure of where to go from here in debugging this. And more importantly, is this even a possible thing to do?
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243
Mar ’25
Is there a way to limit the MusicKit JWT tokens to just the Apple Music API using scopes?
Hi, I'm generating MusicKit JWT tokens on my backend side and using it on the client side to query the Apple Music API. One concern I have is accidentally over issuing the scope of this JWT, resulting in accidental access more services than intended like DeviceCheck or APNS. Other than using separate keys for MusicKit and other services, is there a way to limit the generated JWT to only the Apple Music API (https://api.music.apple.com/v1/*) using the JWT payload scope?
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91
May ’25
Intermittent Screen Lock During Appium Tests on iOS 18 Simulator
I am running Appium tests on an iOS 18 simulator, and I am encountering an intermittent issue where the device screen gets locked unexpectedly during the tests. The Appium logs show no errors or unusual activity, and all commands appear to be executed successfully. However, upon reviewing the device logs, I see entries related to the lock event, but the exact cause remains unclear. SpringBoard: (SpringBoard) [com.apple.SpringBoard:Common] lockUIFromSource:Boot options:{ SBUILockOptionsLockAutomaticallyKey: 1, SBUILockOptionsForceLockKey: 1, SBUILockOptionsUseScreenOffModeKey: 0 } SpringBoard: (SpringBoard) [com.apple.SpringBoard:Common] -[SBTelephonyManager inCall] 0 SpringBoard: (SpringBoard) [com.apple.SpringBoard:Common] LockUI from source: Now locking Has anyone experienced similar behavior with Appium on iOS 18, or could there be a setting or configuration in the simulator that is causing this issue?
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86
Apr ’25
Localized Folder Created After Installing App with Same Name as Existing Application
I have two macOS applications: Application A, named My App.app with the bundle ID com.comp.myapp, and Application B, named My App.app with the bundle ID com.comp.myapp2. Both applications have the same name. Application A is installed at /Applications/My App.app. When I run the installer for Application B, it gets installed in a folder at /Applications/My App.localized/My App.app. Even if I remove Application A using the preinstall script of Application B's installer, the result remains the same. Does the installer determine the installation path with the new folder before the preinstall script executes? How can it be addressed so the new folder will not be created? Notes: We have a composite package that contains multiple components. Instead of just running pkgbuild, we use our own components.plist rather than a synthesized one. The components.plist is attached. The PackageInfo for Application B is also attached. components.plist PackageInfo packageInfo.xml components.plist
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Nov ’24
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
Understanding Mach-O Symbols
This posts collects together a bunch of information about the symbols found in a Mach-O file. It assumes the terminology defined in An Apple Library Primer. If you’re unfamiliar with a term used here, look there for the definition. If you have any questions or comments about this, start a new thread in the Developer Tools & Services > General topic area and tag it with Linker. Share and Enjoy — Quinn “The Eskimo!” @ Developer Technical Support @ Apple let myEmail = "eskimo" + "1" + "@" + "apple.com" Understanding Mach-O Symbols Every Mach-O file has a symbol table. This symbol table has many different uses: During development, it’s written by the compiler. And both read and written by the linker. And various other tools. During execution, it’s read by the dynamic linker. And also by various APIs, most notably dlsym. The symbol table is an array of entries. The format of each entry is very simple, but they have been used and combined in various creative ways to achieve a wide range of goals. For example: In a Mach-O object file, there’s an entry for each symbol exported to the linker. In a Mach-O image, there’s an entry for each symbol exported to the dynamic linker. And an entry for each symbol imported from dynamic libraries. Some entries hold information used by the debugger. See Debug Symbols, below. Examining the Symbol Table There are numerous tools to view and manipulate the symbol table, including nm, dyld_info, symbols, strip, and nmedit. Each of these has its own man page. A good place to start is nm: % nm Products/Debug/TestSymTab U ___stdoutp 0000000100000000 T __mh_execute_header U _fprintf U _getpid 0000000100003f44 T _main 0000000100008000 d _tDefault 0000000100003ecc T _test 0000000100003f04 t _testHelper Note In the examples in this post, TestSymTab is a Mach-O executable that’s formed by linking two Mach-O object files, main.o and TestCore.o. There are three columns here, and the second is the most important. It’s a single letter indicating the type of the entry. For example, T is a code symbol (in Unix parlance, code is in the text segment), D is a data symbol, and so on. An uppercase letter indicates that the symbol is visible to the linker; a lowercase letter indicates that it’s internal. An undefined (U) symbol has two potential meanings: In a Mach-O image, the symbol is typically imported from a specific dynamic library. The dynamic linker connects this import to the corresponding exported symbol of the dynamic library at load time. In a Mach-O object file, the symbol is undefined. In most cases the linker will try to resolve this symbol at link time. Note The above is a bit vague because there are numerous edge cases in how the system handles undefined symbols. For more on this, see Undefined Symbols, below. The first column in the nm output is the address associated with the entry, or blank if an address is not relevant for this type of entry. For a Mach-O image, this address is based on the load address, so the actual address at runtime is offset by the slide. See An Apple Library Primer for more about those concepts. The third column is the name for this entry. These names have a leading underscore because that’s the standard name mangling for C. See An Apple Library Primer for more about name mangling. The nm tool has a lot of formatting options. The ones I use the most are: -m — This prints more information about each symbol table entry. For example, if a symbol is imported from a dynamic library, this prints the library name. For a concrete example, see A Deeper Examination below. -a — This prints all the entries, including debug symbols. We’ll come back to that in the Debug Symbols section, below. -p — By default nm sorts entries by their address. This disables that sort, causing nm to print the entries in the order in which they occur in the symbol table. -x — This outputs entries in a raw format, which is great when you’re trying to understand what’s really going on. See Raw Symbol Information, below, for an example of this. A Deeper Examination To get more information about each symbol table, run nm with the -m option: % nm -m Products/Debug/TestSymTab (undefined) external ___stdoutp (from libSystem) 0000000100000000 (__TEXT,__text) [referenced dynamically] external __mh_execute_header (undefined) external _fprintf (from libSystem) (undefined) external _getpid (from libSystem) 0000000100003f44 (__TEXT,__text) external _main 0000000100008000 (__DATA,__data) non-external _tDefault 0000000100003ecc (__TEXT,__text) external _test 0000000100003f04 (__TEXT,__text) non-external _testHelper This contains a world of extra information about each entry. For example: You no longer have to remember cryptic single letter codes. Instead of U, you get undefined. If the symbol is imported from a dynamic library, it gives the name of that dynamic library. Here we see that _fprintf is imported from the libSystem library. It surfaces additional, more obscure information. For example, the referenced dynamically flag is a flag used by the linker to indicate that a symbol is… well… referenced dynamically, and thus shouldn’t be dead stripped. Undefined Symbols Mach-O’s handling of undefined symbols is quite complex. To start, you need to draw a distinction between the linker (aka the static linker) and the dynamic linker. Undefined Symbols at Link Time The linker takes a set of files as its input and produces a single file as its output. The input files can be Mach-O images or dynamic libraries [1]. The output file is typically a Mach-O image [2]. The goal of the linker is to merge the object files, resolving any undefined symbols used by those object files, and create the Mach-O image. There are two standard ways to resolve an undefined symbol: To a symbol exported by another Mach-O object file To a symbol exported by a dynamic library In the first case, the undefined symbol disappears in a puff of linker magic. In the second case, it records that the generated Mach-O image depends on that dynamic library [3] and adds a symbol table entry for that specific symbol. That entry is also shown as undefined, but it now indicates the library that the symbol is being imported from. This is the core of the two-level namespace. A Mach-O image that imports a symbol records both the symbol name and the library that exports the symbol. The above describes the standard ways used by the linker to resolve symbols. However, there are many subtleties here. The most radical is the flat namespace. That’s out of scope for this post, because it’s a really bad option for the vast majority of products. However, if you’re curious, the ld man page has some info about how symbol resolution works in that case. A more interesting case is the -undefined dynamic_lookup option. This represents a halfway house between the two-level namespace and the flat namespace. When you link a Mach-O image with this option, the linker resolves any undefined symbols by adding a dynamic lookup undefined entry to the symbol table. At load time, the dynamic linker attempts to resolve that symbol by searching all loaded images. This is useful if your software works on other Unix-y platforms, where a flat namespace is the norm. It can simplify your build system without going all the way to the flat namespace. Of course, if you use this facility and there are multiple libraries that export that symbol, you might be in for a surprise! [1] These days it’s more common for the build system to pass a stub library (.tbd) to the linker. The effect is much the same as passing in a dynamic library. In this discussion I’m sticking with the old mechanism, so just assume that I mean dynamic library or stub library. If you’re unfamiliar with the concept of a stub library, see An Apple Library Primer. [2] The linker can also merge the object files together into a single object file, but that’s relatively uncommon operation. For more on that, see the discussion of the -r option in the ld man page. [3] It adds an LC_LOAD_DYLIB load command with the install name from the dynamic library. See Dynamic Library Identification for more on that. Undefined Symbols at Load Time When you load a Mach-O image the dynamic linker is responsible for finding all the libraries it depends on, loading them, and connecting your imports to their exports. In the typical case the undefined entry in your symbol table records the symbol name and the library that exports the symbol. This allows the dynamic linker to quickly and unambiguously find the correct symbol. However, if the entry is marked as dynamic lookup [1], the dynamic linker will search all loaded images for the symbol and connect your library to the first one it finds. If the dynamic linker is unable to find a symbol, its default behaviour is to fail the load of the Mach-O image. This changes if the symbol is a weak reference. In that case, the dynamic linking continues to load the image but sets the address of the symbol to NULL. See Weak vs Weak vs Weak, below, for more about this. [1] In this case nm shows the library name as dynamically looked up. Weak vs Weak vs Weak Mach-O supports two different types of weak symbols: Weak references (aka weak imports) Weak definitions IMPORTANT If you use the term weak without qualification, the meaning depends on your audience. App developers tend to assume that you mean a weak reference whereas folks with a C++ background tend to assume that you mean a weak definition. It’s best to be specific. Weak References Weak references support the availability mechanism on Apple platforms. Most developers build their apps with the latest SDK and specify a deployment target, that is, the oldest OS version on which their app runs. Within the SDK, each declaration is annotated with the OS version that introduced that symbol [1]. If the app uses a symbol introduced later than its deployment target, the compiler flags that import as a weak reference. The app is then responsible for not using the symbol if it’s run on an OS release where it’s not available. For example, consider this snippet: #include <xpc/xpc.h> void testWeakReference(void) { printf("%p\n", xpc_listener_set_peer_code_signing_requirement); } The xpc_listener_set_peer_code_signing_requirement function is declared like so: API_AVAILABLE(macos(14.4)) … int xpc_listener_set_peer_code_signing_requirement(…); The API_AVAILABLE macro indicates that the symbol was introduced in macOS 14.4. If you build this code with the deployment target set to macOS 13, the symbol is marked as a weak reference: % nm -m Products/Debug/TestWeakRefC … (undefined) weak external _xpc_listener_set_peer_code_signing_requirement (from libSystem) If you run the above program on macOS 13, it’ll print NULL (actually 0x0). Without support for weak references, the dynamic linker on macOS 13 would fail to load the program because the _xpc_listener_set_peer_code_signing_requirement symbol is unavailable. [1] In practice most of the SDK’s declarations don’t have availability annotations because they were introduced before the minimum deployment target supported by that SDK. Weak definitions Weak references are about imports. Weak definitions are about exports. A weak definition allows you to export a symbol from multiple images. The dynamic linker coalesces these symbol definitions. Specifically: The first time it loads a library with a given weak definition, the dynamic linker makes it the primary. It registers that definition such that all references to the symbol resolve to it. This registration occurs in a namespace dedicated to weak definitions. That namespace is flat. Any subsequent definitions of that symbol are ignored. Weak definitions are weird, but they’re necessary to support C++’s One Definition Rule in a dynamically linked environment. IMPORTANT Weak definitions are not just weird, but also inefficient. Avoid them where you can. To flush out any unexpected weak definitions, pass the -warn_weak_exports option to the static linker. The easiest way to create a weak definition is with the weak attribute: __attribute__((weak)) void testWeakDefinition(void) { } IMPORTANT The C++ compiler can generate weak definitions without weak ever appearing in your code. This shows up in nm like so: % nm -m Products/Debug/TestWeakDefC … 0000000100003f40 (__TEXT,__text) weak external _testWeakDefinition … The output is quite subtle. A symbol flagged as weak external is either a weak reference or a weak definition depending on whether it’s undefined or not. For clarity, use dyld_info instead: % dyld_info -imports -exports Products/Debug/TestWeakRefC Products/Debug/TestWeakDefC [arm64]: … -imports: … 0x0001 _xpc_listener_set_peer_code_signing_requirement [weak-import] (from libSystem) % dyld_info -imports -exports Products/Debug/TestWeakDefC Products/Debug/TestWeakDefC [arm64]: -exports: offset symbol … 0x00003F40 _testWeakDefinition [weak-def] … … Here, weak-import indicates a weak reference and weak-def a weak definition. Weak Library There’s one final confusing use of the term weak, that is, weak libraries. A Mach-O image includes a list of imported libraries and a list of symbols along with the libraries they’re imported from. If an image references a library that’s not present, the dynamic linker will fail to load the library even if all the symbols it references in that library are weak references. To get around this you need to mark the library itself as weak. If you’re using Xcode it will often do this for your automatically. If it doesn’t, mark the library as optional in the Link Binary with Libraries build phase. Use otool to see whether a library is required or optional. For example, this shows an optional library: % otool -L Products/Debug/TestWeakRefC Products/Debug/TestWeakRefC: /usr/lib/libEndpointSecurity.dylib (… 511.60.5, weak) … In the non-optional case, there’s no weak indicator: % otool -L Products/Debug/TestWeakRefC Products/Debug/TestWeakRefC: /usr/lib/libEndpointSecurity.dylib (… 511.60.5) … Debug Symbols or Why the DWARF still stabs. (-: Historically, all debug information was stored in symbol table entries, using a format knows as stabs. This format is now obsolete, having been largely replaced by DWARF. However, stabs symbols are still used for some specific roles. Note See <mach-o/stab.h> and the stab man page for more about stabs on Apple platforms. See stabs and DWARF for general information about these formats. In DWARF, debug symbols aren’t stored in the symbol table. Rather, debug information is stored in various __DWARF sections. For example: % otool -l Intermediates.noindex/TestSymTab.build/Debug/TestSymTab.build/Objects-normal/arm64/TestCore.o | grep __DWARF -B 1 sectname __debug_abbrev segname __DWARF … The compiler inserts this debug information into the Mach-O object file that it creates. Eventually this Mach-O object file is linked into a Mach-O image. At that point one of two things happens, depending on the Debug Information Format build setting. During day-to-day development, set Debug Information Format to DWARF. When the linker creates a Mach-O image from a bunch of Mach-O object files, it doesn’t do anything with the DWARF information in those objects. Rather, it records references to the source objects files into the final image. This is super quick. When you debug that Mach-O image, the debugger finds those references and uses them to locate the DWARF information in the original Mach-O object files. Each reference is stored in a stabs OSO symbol table entry. To see them, run nm with the -a option: % nm -a Products/Debug/TestSymTab … 0000000000000000 - 00 0001 OSO …/Intermediates.noindex/TestSymTab.build/Debug/TestSymTab.build/Objects-normal/arm64/TestCore.o 0000000000000000 - 00 0001 OSO …/Intermediates.noindex/TestSymTab.build/Debug/TestSymTab.build/Objects-normal/arm64/main.o … Given the above, the debugger knows to look for DWARF information in TestCore.o and main.o. And notably, the executable does not contain any DWARF sections: % otool -l Products/Debug/TestSymTab | grep __DWARF -B 1 % When you build your app for distribution, set Debug Information Format to DWARF with dSYM File. The executable now contains no DWARF information: % otool -l Products/Release/TestSymTab | grep __DWARF -B 1 % Xcode runs dsymutil tool to collect the DWARF information, organise it, and export a .dSYM file. This is actually a document package, within which is a Mach-O dSYM companion file: % find Products/Release/TestSymTab.dSYM Products/Release/TestSymTab.dSYM Products/Release/TestSymTab.dSYM/Contents … Products/Release/TestSymTab.dSYM/Contents/Resources/DWARF Products/Release/TestSymTab.dSYM/Contents/Resources/DWARF/TestSymTab … % file Products/Release/TestSymTab.dSYM/Contents/Resources/DWARF/TestSymTab Products/Release/TestSymTab.dSYM/Contents/Resources/DWARF/TestSymTab: Mach-O 64-bit dSYM companion file arm64 That file contains a copy of the the DWARF information from all the original Mach-O object files, optimised for use by the debugger: % otool -l Products/Release/TestSymTab.dSYM/Contents/Resources/DWARF/TestSymTab | grep __DWARF -B 1 … sectname __debug_line segname __DWARF … Raw Symbol Information As described above, each Mach-O file has a symbol table that’s an array of symbol table entries. The structure of each entry is defined by the declarations in <mach-o/nlist.h> [1]. While there is an nlist man page, the best documentation for this format is the the comments in the header itself. Note The terms nlist stands for name list and dates back to truly ancient versions of Unix. Each entry is represented by an nlist_64 structure (nlist for 32-bit Mach-O files) with five fields: n_strx ‘points’ to the string for this entry. n_type encodes the entry type. This is actually split up into four subfields, as discussed below. n_sect is the section number for this entry. n_desc is additional information. n_value is the address of the symbol. The four fields within n_type are N_STAB (3 bits), N_PEXT (1 bit), N_TYPE (3 bits), and N_EXT (1 bit). To see these raw values, run nm with the -x option: % nm -a -x Products/Debug/TestSymTab … 0000000000000000 01 00 0300 00000036 _getpid 0000000100003f44 24 01 0000 00000016 _main 0000000100003f44 0f 01 0000 00000016 _main … This prints a column for n_value, n_type, n_sect, n_desc, and n_strx. The last column is the string you get when you follow the ‘pointer’ in n_strx. The mechanism used to encode all the necessary info into these fields is both complex and arcane. For the details, see the comments in <mach-o/nlist.h> and <mach-o/stab.h>. However, just to give you a taste: The entry for getpid has an n_type field with just the N_EXT flag set, indicating that this is an external symbol. The n_sect field is 0, indicating a text symbol. And n_desc is 0x0300, with the top byte indicating that the symbol is imported from the third dynamic library. The first entry for _main has an n_type field set to N_FUN, indicating a stabs function symbol. The n_desc field is the line number, that is, line 22. The second entry for _main has an n_type field with N_TYPE set to N_SECT and the N_EXT flag set, indicating a symbol exported from a section. In this case the section number is 1, that is, the text section. [1] There is also an <nlist.h> header that defines an API that returns the symbol table. The difference between <nlist.h> and <mach-o/nlist.h> is that the former defines an API whereas the latter defines the Mach-O on-disk format. Don’t include both; that won’t end well!
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Mar ’25
On-demand resource exporting?
I'm a newbie to on-demand resources and I feel like I'm missing something very obvious. I've successfully tagged and set up ODR in my Xcode project, but now I want to upload the assets to my own server so I can retrieve them from within the app, and I can't figure out how to export the files I need. I'm following the ODR Guide and I'm stuck at Step #4, after I've selected my archive in the Archives window it says to "Click the Export button", but this is what I see: As shown in the screenshot, there is no export button visible. I have tried different approaches, including distributing to appstore connect, and doing a local development release. The best I've been able to do is find a .assetpack folder inside the archive package through the finder, but uploading that, or the asset.car inside it, just gives me a "cannot parse response" error from the ODR loading code. I've verified I uploaded those to the correct URL. Can anyone walk me through how to save out the file(s) I need, in a form I can just upload to my server? Thanks, Pete
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May ’25