This is an auto-filled bug because dev-lang/mercury-extras does not respect LDFLAGS. The issue was originally discovered on amd64, but it may be reproducible on other arches as well. If you think that a different summary clarifies the issue better, feel free to change it. Attached build log and emerge --info. NOTE: To reproduce this issue you may want to set LDFLAGS="${LDFLAGS} -Wl,--defsym=__gentoo_check_ldflags__=0". If this is not something about c/c++ context you may want to see this bug as an hint to hide the QA warning where is not possible to respect LDFLAGS.
Created attachment 639020 [details] build.log build log and emerge --info
This is now fixed in git with mercury-extras-20.01.2. Thanks for reporting this bug.