llvm_bin uses same universal darwin archive for arm as for x86_64.

Allow to override target architecture sufix in archive name in tgz_package.
tgz_package uses build platform for naming archives.
When build packages for multiple architectures like x86_64 and arm, then the archive name is not correct.
Update the script of tgz_package to check for configuration option `ohai['target_arch']` as target arch name.

It allows to specify architecture in project like:

```
ohai['target_arch'] = 'universal'
dependency 'tgz_package'
```

Also introduces Github Action to build llvm from scratch, similar to circle ci.

.github/workflows/llvm.yml

@@ -0,0 +1,79 @@
+name: Darwin LLVM build
+
+on:
+  workflow_dispatch:
+    inputs:
+      logLevel:
+        description: 'Log level'
+        required: false
+        default: 'warn'
+        type: choice
+        options:
+          - info
+          - warn
+          - debug
+  push:
+    branches:
+      - 267-llvm_bin-universal
+      - '*build-llvm*'
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+env:
+  LLVM_VERSION: 15.0.7
+  MACOSX_DEPLOYMENT_TARGET: 10.11
+  LOG_LEVEL: ${{ inputs.logLevel || 'warn' }}
+
+jobs:
+  llvm-build:
+    runs-on: macos-11
+    defaults:
+      run:
+        working-directory: ./omnibus
+
+    steps:
+      - name: Select Xcode
+        uses: maxim-lobanov/setup-xcode@v1
+        with:
+          xcode-version: '13.2.1'
+
+      - name: Download sources
+        uses: actions/checkout@v4
+
+      - name: Update development environment
+        run: |
+          brew update
+          brew install --display-times pkgconfig libtool cmake
+
+      - name: Prepare folders
+        run: |
+          sudo mkdir -p /opt/llvm
+          sudo chown $(whoami) /opt/llvm/
+          sudo mkdir -p /var/cache
+          sudo chown $(whoami) /var/cache
+
+      - name: Install omnibus
+        run: bundle check || bundle install
+
+      - name: Build llvm
+        run: bundle exec omnibus build llvm --log-level ${{ env.LOG_LEVEL }} --override use_git_caching:false
+
+        # Reference: https://docs.github.com/en/actions/using-workflows/workflow-commands-for-github-actions#environment-files
+      - name: Extract the package name to be used for the artifact name
+        run: |
+          cd pkg
+          filename=$(ls -1 llvm-*.tar.gz)
+          echo "ARTIFACT_NAME=${filename%.tar.gz}" >> "$GITHUB_ENV"
+
+        # When an Artifact is uploaded, all the files are assembled into an immutable Zip archive.
+        # https://github.com/actions/upload-artifact#zip-archives
+      - name: Upload artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: ${{ env.ARTIFACT_NAME }}
+          path: omnibus/pkg/*.tar.gz
+          retention-days: 1
+          if-no-files-found: error
+          compression-level: 0 # package is already compressed

darwin/README.md

@@ -9,12 +9,18 @@ The whole process is automated using a `Makefile`.
 * `pkgconfig`, `libtool` (Can be installed by `$ brew install pkgconfig libtool`)
 * Own `/opt/crystal`, `/var/cache`.
 
-```
+```shell
 sudo mkdir -p /opt/crystal
 sudo chown $(whoami) /opt/crystal/
 sudo mkdir -p /var/cache
 sudo chown $(whoami) /var/cache
 ```
+* Optional: If you need to build LLVM, ensure the existence of the /opt/llvm directory.
+
+```shell
+sudo mkdir -p /opt/llvm
+sudo chown $(whoami) /opt/llvm/
+```
 
 # Getting started
 

omnibus/config/projects/llvm.rb

@@ -18,6 +18,9 @@ def valid_cmake_version?
 
 dependency 'cmake' unless valid_cmake_version?
 dependency 'llvm'
+
+# Requires for tgz_package to generate a proper archive name with sufix universal.
+ohai['target_arch'] = 'universal'
 dependency 'tgz_package' if macos? || mac_os_x? || centos?
 
 exclude '\.git*'

omnibus/config/software/llvm_bin.rb

@@ -18,7 +18,11 @@
   raise "llvm_bin not supported"
 end
 
-source url: "http://crystal-lang.s3.amazonaws.com/llvm/llvm-#{version}-#{ohai['os']}-#{ohai['kernel']['machine']}.tar.gz",
+platform = ohai['os']
+# Currently, it is considered `universal` based on the alterations made in the commit 'ed5f1f97e0a67157d886dd6675902e35199a1ab3'
+arch = "x86_64"
+
+source url: "http://crystal-lang.s3.amazonaws.com/llvm/llvm-#{version}-#{platform}-#{arch}.tar.gz",
        md5: source_md5
 
 relative_path "llvm-#{version}"

omnibus/config/software/tgz_package.rb

@@ -4,10 +4,12 @@
 
 build do
   block do
+    platform = ohai['os']
+    target_arch = ohai['target_arch'] || ohai['kernel']['machine']
     destination = File.expand_path('pkg', Omnibus::Config.project_root)
     version = "#{project.build_version}-#{project.build_iteration}"
     version.gsub!("/", "-")
-    tgz_name = "#{project.name}-#{version}-#{ohai['os']}-#{ohai['kernel']['machine']}.tar.gz"
+    tgz_name = "#{project.name}-#{version}-#{platform}-#{target_arch}.tar.gz"
     if macos? || mac_os_x?
       transform = "-s /./#{project.name}-#{version}/"
     else
@@ -16,5 +18,10 @@
 
     command "tar czf #{destination}/#{tgz_name} #{transform} -C #{install_dir} .",
       env: {"COPYFILE_DISABLE" => "1"}
+
+    # NOTE: For environments not in English, git_cache function expected to see message 
+    #       from git `nothing to commit`, otherwise it raises the error.
+    #       It creates a empty file to commit something.
+    command "date > #{install_dir}/tgz_package_done.log"
   end
 end