gem install debugger Fetching: columnize-0.8.9.gem (100%) Successfully installed columnize-0.8.9 Fetching: debugger-linecache-1.2.0.gem (100%) Successfully installed debugger-linecache-1.2.0 Fetching: debugger-1.6.8.gem (100%) Building native extensions. This could take a while... Successfully installed debugger-1.6.8 Parsing documentation for columnize-0.8.9 Installing ri documentation for columnize-0.8.9 Parsing documentation for debugger-1.6.8 unable to convert "\x96" from ASCII-8BIT to UTF-8 for ../../extensions/x86_64-linux/2.0.0/debugger-1.6.8/ruby_debug.so, skipping unable to convert "\x96" from ASCII-8BIT to UTF-8 for lib/ruby_debug.so, skipping Installing ri documentation for debugger-1.6.8 Parsing documentation for debugger-linecache-1.2.0 Installing ri documentation for debugger-linecache-1.2.0 3 gems installed

这个有 2 个 unable to convert 请问，怎么解决？