Add CI job to build C sources with various compiler versions

* See #4048

Author: eregon

.github/workflows/main.yml

@@ -174,6 +174,18 @@ jobs:
       env:
         PRISM_BUILD_MINIMAL: "1"
 
+  build-with-various-compilers:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v6
+    - name: Set up Ruby
+      uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: ruby
+        bundler-cache: true
+    - name: Build with various compilers
+      run: bundle exec rake build_in_docker
+
   build-java:
     runs-on: ubuntu-latest
     env:

Rakefile

@@ -76,3 +76,21 @@ namespace :build do
   desc "Build a development version of the gem"
   task dev: ["build:dev_version_set", "build", "build:dev_version_clear"]
 end
+
+task :build_in_docker => :templates do
+  # Versions from https://github.com/ruby/ruby/blob/master/.github/workflows/compilers.yml
+  compilers = (7..15).map { |v| "gcc-#{v}" }
+  compilers.each do |compiler|
+    dockerfile = <<~DOCKERFILE
+    FROM ghcr.io/ruby/ruby-ci-image:#{compiler}
+    USER root
+    ADD . /prism
+    WORKDIR /prism
+    RUN #{compiler} --version
+    RUN make CC=#{compiler}
+    DOCKERFILE
+    File.write 'Dockerfile', dockerfile
+    sh "docker build ."
+    rm 'Dockerfile'
+  end
+end