Are you tired of wrestling with Cmake 3.30 and the Xcode generator? Have you noticed that the trusty $(ARCHS_STANDARD) variable no longer works as expected? You’re not alone! In this article, we’ll delve into the mystery behind this issue, explore its implications, and provide you with a comprehensive guide on how to overcome this hurdle.
What’s Changed in Cmake 3.30?
With the release of Cmake 3.30, the development team introduced several significant changes to improve the build system. One of these changes involves the way Cmake handles the Xcode generator. Unfortunately, this update has also brought about some unexpected side effects, including the breakage of $(ARCHS_STANDARD) variable.
In Cmake, the $(ARCHS_STANDARD) variable is used to specify the target architectures for your project. This variable is typically set by the Xcode generator to include the standard architectures (e.g., armv7, arm64, x86_64, and i386). However, with Cmake 3.30, the $(ARCHS_STANDARD) variable is no longer automatically set by the Xcode generator.
Implications of the Broken $(ARCHS_STANDARD) Variable
The failure of $(ARCHS_STANDARD) variable can have far-reaching implications for your project. Here are a few consequences you might encounter:
- Inconsistent Builds: Without the $(ARCHS_STANDARD) variable, your project may not build consistently across different architectures. This can lead to errors, crashes, or unexpected behavior in your application.
- Target Architecture Issues: If you’re targeting specific architectures (e.g., arm64 or x86_64), you may need to manually specify these architectures in your CmakeLists.txt file. This can become cumbersome and prone to errors.
- Compatibility Problems: Older projects that relied on $(ARCHS_STANDARD) may break when upgraded to Cmake 3.30. This can cause compatibility issues with older versions of Xcode or other development environments.
Workarounds and Solutions
Don’t panic! We’ve got you covered. Here are some workarounds and solutions to help you overcome the broken $(ARCHS_STANDARD) variable:
1. Manual Architecture Specification
One way to address this issue is to manually specify the target architectures in your CmakeLists.txt file. You can do this by setting the CMAKE_OSX_ARCHITECTURES variable:
set(CMAKE_OSX_ARCHITECTURES "arm64;x86_64;i386")
This approach requires manual maintenance and can become tedious for complex projects. However, it’s a viable solution for smaller projects or those with specific architecture requirements.
2. Using Cmake’s built-in Architecture Detection
Cmake 3.30 introduced a new module called CMakeAppleDeviceSystem, which provides built-in architecture detection. You can use this module to automatically detect the target architectures:
include(CMakeAppleDeviceSystem)
set(CMAKE_OSX_ARCHITECTURES ${CMAKE_APPLE_DEVICE_ARCHITECTURES})
This approach is more elegant and flexible than manual specification, but it requires Cmake 3.30 or later.
3. Creating a Custom Cmake Module
For more complex scenarios or to maintain compatibility with older projects, you can create a custom Cmake module to handle the architecture detection. Here’s an example:
include(CMakeMacroArchitecture)
macro(MyProjectDetectArchitectures)
if(CMAKE_SYSTEM_NAME STREQUAL "Darwin")
set(CMAKE_OSX_ARCHITECTURES "arm64;x86_64;i386")
endif()
endmacro()
This custom module can be included in your CmakeLists.txt file to automatically detect and set the target architectures:
include(MyProjectCMakeModule)
MyProjectDetectArchitectures()
Troubleshooting and Debugging
When dealing with architecture-related issues, it’s essential to have a solid understanding of Cmake’s architecture detection and the Xcode generator. Here are some tips to help you troubleshoot and debug:
- Check Cmake Variables: Verify that the CMAKE_OSX_ARCHITECTURES variable is set correctly by using the
message()function:message("CMAKE_OSX_ARCHITECTURES: ${CMAKE_OSX_ARCHITECTURES}") - Review Xcode Project Settings: Inspect the Xcode project settings to ensure that the target architectures are correctly specified:
open ${CMAKE_CURRENT_BINARY_DIR}/MyProject.xcodeproj - Consult Cmake Documentation: Refer to the official Cmake documentation for guidance on architecture detection and the Xcode generator:
cmake --help-variable CMAKE_OSX_ARCHITECTURESConclusion
The mysterious case of the broken $(ARCHS_STANDARD) variable in Cmake 3.30 has been solved! By understanding the changes in Cmake 3.30 and applying the workarounds and solutions presented in this article, you can overcome the challenges posed by this issue.
Remember to stay vigilant and adapt to the evolving landscape of Cmake and Xcode. With patience, persistence, and a dash of creativity, you can tame even the most stubborn build systems.
Cmake Version $(ARCHS_STANDARD) Behavior < 3.30 Automatically set by Xcode generator 3.30+ Manually set or detected using CMakeAppleDeviceSystem module We hope this article has been informative and helpful in navigating the complexities of Cmake and Xcode. If you have any questions or need further assistance, please don’t hesitate to ask!
Here is the Frequently Asked Question page about “Cmake 3.30 seems to break use of $(ARCHS_STANDARD) for Xcode Generator”:
Frequently Asked Question
Get answers to your burning questions about Cmake 3.30 and Xcode Generator!
What’s the deal with Cmake 3.30 breaking $(ARCHS_STANDARD) for Xcode Generator?
It’s a known issue! Cmake 3.30 introduced a change that broke the use of $(ARCHS_STANDARD) for Xcode Generator. The good news is that it’s being worked on, and a fix is on the way!
Is there a temporary solution to get $(ARCHS_STANDARD) working again?
Yes, you can downgrade to Cmake 3.23 or earlier, which still supports $(ARCHS_STANDARD). Alternatively, you can try using the CMAKE_OSX_ARCHITECTURES variable as a workaround.
What’s the root cause of this issue?
The issue stems from a change in how Cmake handles architecture settings. In Cmake 3.30, the $(ARCHS_STANDARD) variable is no longer being set, causing issues for Xcode Generator.
When can we expect a fix for this issue?
The Cmake team is working on a patch, but there’s no ETA yet. Keep an eye on the Cmake issue tracker for updates!
Is this issue specific to Xcode Generator or does it affect other generators as well?
As of now, this issue only affects the Xcode Generator. Other generators, such as Visual Studio or Makefiles, are not impacted by this change.
