bin/autoproj_install in autoproj-2.12.1 vs bin/autoproj_install in autoproj-2.13.0

@@ -262,10 +262,10 @@
                  "gem \"autoproj\", \"#{autoproj_version}\"",
                  "gem \"utilrb\", \">= 3.0.1\""].join("\n")
             end
 
             def add_seed_config(path)
-                @config.merge!(YAML.safe_load(File.read(path)))
+                @config.merge!(YAML.safe_load(File.read(path), [Symbol]))
             end
 
             # Parse the provided command line options and returns the non-options
             def parse_options(args = ARGV)
                 options = OptionParser.new do |opt|