If these values do not match exactly, it is because the UTF-8 is invalid
anyway and we counted codepoints differently than oniguruma did. Perhaps it
would be better to error out here, but at least one similar loop already
uses < vs != and since we're off the rails anyway this might be OK. It is
certainly better than overruning the buffer.
Resolves https://github.com/stedolan/jq/issues/1804
Derrick Pallas