Merge pull request #630 from junaruga/wip/print-compiler-version

Print the Ruby and compiler info or the command itself before compiling.

Rakefile

@@ -5,6 +5,8 @@ require 'bundler/gem_tasks'
 begin
   require 'rake/extensiontask'
   Rake::ExtensionTask.new('openssl')
+  # Run the debug_compiler task before the compile task.
+  Rake::Task['compile'].prerequisites.unshift :debug_compiler
 rescue LoadError
   warn "rake-compiler not installed. Run 'bundle install' to " \
     "install testing dependency gems."
@@ -22,6 +24,19 @@ RDoc::Task.new do |rdoc|
 end
 
 task :test => [:compile, :debug]
+
+# Print Ruby and compiler info for debugging purpose.
+task :debug_compiler do
+  ruby '-v'
+  compiler = RbConfig::CONFIG['CC']
+  case compiler
+  when 'gcc', 'clang'
+    sh "#{compiler} --version"
+  else
+    puts "Compiler: #{RbConfig::CONFIG['CC']}"
+  end
+end
+
 task :debug do
   ruby "-I./lib -ropenssl -ve'puts OpenSSL::OPENSSL_VERSION, OpenSSL::OPENSSL_LIBRARY_VERSION'"
 end