cover aggregation bug

[MarkoMin]

Describe the bug Description is here, I thought that the bug is in rebar3, but it probably isn't.

To Reproduce I'm not aware what the actual trigger is, but project that is tested with both proper and ct should exploit the behavior. Coverage for proper and ct independently both look correct! Minimal reproduce is in archive file (notice how line that is considered ignored in independent cases is considered unused in aggregated coverage). To reproduce, run rebar3 ct --cover, rebar3 eunit --cover, rebar3 proper --cover and finally rebar3 cover to look at the results.

Expected behavior

Aggregated coverage should be greater than independent coverages and ignored lines shouldn't be counted as unused

Affected versions OTP 26.1.2

Additional context coverage_repro.tar.gz