message: Exclude unreachable lines from code coverage
  codecov.io does not seem to support lcov regex customization;
  additionally, we can't just replace unreachable with LCOV_LINE_EXCL
  in gcov file - so we have to patch the ##### indicator (which suggests
  the line hasn't been hit) with 1.
  See also
diff: @@ -14,4 +14,6 @@ script:
  - make test cxxstd=c++11 defines=$DEFINES config=release -j2
  - make test cxxstd=c++98 defines=$DEFINES config=debug -j2
  -after_success: bash <(curl -s https://codecov.io/bash) -f pugixml.cpp.gcov
  +after_success:
  + - sed -e "s/#####\(.*\)\(\/\/ unreachable.*\)/ 1\1\2/" -i pugixml.cpp.gcov
  + - bash <(curl -s https://codecov.io/bash) -f pugixml.cpp.gcov
  