The native C++ < and > operators won't handle this correctly, so the
result was different depending on the order of arguments. This is now
fixed by explicitly checking for positive and negative zero values.
Fixes#6589.
SPDX License Identifiers are a more compact / standardized
way of representing file license information.
See: https://spdx.dev/resources/use/#identifiers
This was done with the `ambr` search and replace tool.
ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *
