Enable native comp in Windows native Emacs

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#1

If following the guide and installing native Emacs on Windows from Scoop, the latest versions have native comp enabled but it is unusable due to the lack of a viable libgccjit. The following instructions will install libgccjit and place it on your path so that the Scoop-installed Emacs will have working native compilation.

Warning: This will place a newly installed MSYS2 GCC executable on your path. If you have GCC installed another way it may cause issues. gcm gcc can help debug from a PowerShell terminal.

  1. Install MSYS2
  2. Open MSYS2 MINGW64 terminal from the start menu
  3. Run pacman -S mingw-w64-x86_64-libgccjit
  4. Open up Edit environment variables for your account, edit the Path user variable, and add C:\msys64\mingw64\bin (or replace C:\msys64 with your actual install location, if you chose a non-default)
  5. Native comp should now work! Run doom doctor and check.