Merge pull request #20377 from Homebrew/fix-linkage-checker-file-descriptors

Fix file descriptor leak in Linux LD library path parsing

Library/Homebrew/os/linux/ld.rb

@@ -50,10 +50,17 @@ module OS
         conf_file = Pathname(conf_path)
         return [] unless conf_file.exist?
 
+        @library_paths_cache ||= T.let({}, T.nilable(T::Hash[String, T::Array[String]]))
+        cache_key = conf_file.to_s
+        if (cached_library_path_contents = @library_paths_cache[cache_key])
+          return cached_library_path_contents
+        end
+
         paths = Set.new
         directory = conf_file.realpath.dirname
 
-        conf_file.readlines.each do |line|
+        conf_file.open("r") do |file|
+          file.each_line do |line|
             # Remove comments and leading/trailing whitespace
             line.strip!
             line.sub!(/\s*#.*$/, "")
@@ -71,8 +78,9 @@ module OS
               paths << line
             end
           end
+        end
 
-        paths.to_a
+        @library_paths_cache[cache_key] = paths.to_a
       end
     end
   end