Earlier quoted context omitted.
AFAIK, you can't specify several outputs per rule in GNU Make without relying on horribly complex workarounds. It's actually the feature I miss the most in it.
Is this too complex and/or insufficient? https://www.gnu.org/software/automake/manual/html_node/Multi...
That doesn't really look like "handling it" by any sensible definition. That looks like a huge kludgy workaround, almost like user implementing a build system inside the build system. (I mean, wtf, asking the user to implement a lock-and-set operation inside their build?)