Mac os: Rails broken - bundle not working - ovirt-engine-sdk - ERROR: Failed to build gem native extension

3 min read 04-10-2024

Mac os: Rails broken - bundle not working - ovirt-engine-sdk - ERROR: Failed to build gem native extension

Rails on Mac: Fixing "Failed to Build Gem Native Extension" for ovirt-engine-sdk

Have you encountered the frustrating "ERROR: Failed to build gem native extension" error while trying to run your Rails application on your Mac? This usually happens when you're using a gem that requires native code compilation, like the ovirt-engine-sdk. This article will break down this common problem, explain why it happens, and walk you through the steps to fix it.

Scenario: The Frustration Begins

Let's say you're developing a Rails app that interacts with an oVirt engine, a virtualization management platform. You've installed the ovirt-engine-sdk gem, but when you try to run bundle install or start your application, you see the following error:

ERROR:  Failed to build gem native extension.

......

/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/bin/ruby -r ./siteconf20230313-15567-1o9r3m6.rb extconf.rb 
mkmf.rb can't find header files for ruby at /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/universal-darwin20
*** extconf.rb failed ***

This error message signals that the gem compilation process cannot find the necessary Ruby header files. This is often a consequence of conflicting Ruby installations or incorrect environment configurations on macOS.

Demystifying the Error: Why This Happens

Here's a simplified breakdown of the cause:

Ruby Versions: Mac comes pre-installed with Ruby, but you might have installed another version through tools like RVM or Homebrew. These installations can lead to conflicting paths for the Ruby headers, confusing the ovirt-engine-sdk gem's build process.
Environment Configuration: The ovirt-engine-sdk gem might rely on specific libraries or development tools that aren't installed or configured correctly.
Missing Dependencies: Certain libraries or development tools might be missing, preventing the gem from compiling properly.

Solutions: Reclaiming Your Rails Sanity

Here's a step-by-step guide to resolving the "Failed to Build Gem Native Extension" error:

Verify Ruby Version:
- Check which version of Ruby is used by your project:
```
bundle env
```
- Identify your system's primary Ruby version:
```
ruby -v
```
- If they differ, ensure your project is using the correct Ruby version. Use rvm use <version> or brew switch <version> to set the desired Ruby version for your project.
Install Required Dependencies:
- Install development tools:
```
xcode-select --install 
```
- Make sure you have the necessary libraries:
```
brew install openssl libffi
```
Clean up Your Ruby Environment:
- Clear your gem cache:
```
gem clean
```
- Remove and reinstall the ovirt-engine-sdk gem:
```
gem uninstall ovirt-engine-sdk
gem install ovirt-engine-sdk
```
Check for Conflicts:
- If you're using RVM, ensure it's properly set up and there are no conflicting Ruby versions.
- If you're using Homebrew, check for any conflicting packages related to Ruby or development tools.
Try Recompiling:
- Run bundle install again. This will attempt to rebuild the gem using the corrected environment.
Advanced Solutions:
- Install the ovirt-engine-sdk gem from a specific source:
```
gem install ovirt-engine-sdk --source <source_url>
```
- Manually adjust the extconf.rb file in the ovirt-engine-sdk gem's directory to point to the correct Ruby header files. This is a more advanced solution and should only be attempted if other methods fail.

Additional Tips:

Restart your terminal after making changes. This ensures the new environment settings are loaded.
Consider using a virtual environment tool like RVM or Bundler to manage your Ruby environment. This can help prevent conflicts and simplify dependency management.

Wrapping Up:

Getting the "Failed to Build Gem Native Extension" error is a common frustration when using gems that require native code compilation. By understanding the causes and following the solutions outlined in this article, you can get your Rails application working smoothly again and avoid this frustrating problem in the future.