I see what you mean. Could you file an issue in the issue tracker? I don't see these at square because we suppress all that output with:

[reporting]
# This cuts down on the verbosity of pants output
# Comment out these lines to see warnings and other output from javac
console_label_format: {
    'COMPILER' : 'SUPPRESS',
  }
console_tool_output_format: {
    'COMPILER' : 'SUPPRESS',
    'PREP': 'INDENT',
  }