How can I fix native extension build errors when installing Rails on Windows 11 ARM64?

Below is an outline of what to look for and some suggestions:

What to Look for in mkmf.log

When you open mkmf.log (in this case at
C:/Ruby34-arm/lib/ruby/gems/3.4.0/extensions/aarch64-mingw-ucrt/3.4.0/nokogiri-1.18.2/mkmf.log), search for the following:

• Missing header files or libraries:
  Look for error lines such as “cannot find” or “no such file or directory” that indicate a header (e.g. libxml2, libxslt, libiconv) or library is missing.

• Linker errors:
  Check for undefined symbols or linking errors. These messages usually show which library the linker could not find (such as “-lxml2” or “-lxslt”).

• Compiler flags issues:
  Sometimes the log shows that the flags passed to the compiler are incorrect or not appropriate for your system (ARM64 Windows vs. typical x86 builds).

The goal is to identify which dependency or build flag is causing the nokogiri native extension (and hence rails installation) to fail.

Steps to Consider

1. Install or Verify Dependencies:
   For nokogiri the common dependencies are:

   • libxml2 and libxslt (as well as their development headers)
   • zlib and libiconv

   While your MSYS2 installation attempted to install these, the error with “ibxml2-devel” (which appears to be a typo or incorrect package name) suggests that at least one dependency was not installed. On Windows, ensure you install the packages with names exactly matching what MSYS2’s repository provides (e.g. libxml2, libxml2-devel, libxslt, libxslt-devel).

2. Use System Libraries:
   Sometimes, installing nokogiri by telling it to use system libraries helps. You could try:

   SHCopied
   gem install nokogiri --platform=ruby -- --use-system-libraries

   Then proceed with installing Rails.

3. Ruby Installer for Windows and Precompiled Gems:
   Ruby Installer on Windows sometimes provides precompiled versions of popular gems. Check if there’s a precompiled version for nokogiri on Windows ARM64. If not, you may be stuck trying to compile from source—and then you’ll need to work through the dependency installation manually.

4. Consider Alternative Environment:
   As you experienced, installing Ruby on Ubuntu (or another Linux distribution) can circumvent these issues since the package management and dependencies are generally more straightforward on those platforms.

Summary

• Review mkmf.log: Focus on error messages regarding missing headers, library files, or linking issues.
• Identify and install missing packages: Ensure the correct names are used (e.g. libxml2-devel might need to be installed as something else in MSYS2).
• Try using system libraries when installing nokogiri.

This way you’ll have a clearer indication of what’s missing, which is the key to solving the build error.