+cc Filipe who apparently did the update

last commit is here, but I cannot see anything related to RPM_OPT_FLAGS, I need to look further to see whats happening.

http://pkgs.fedoraproject.org/cgit/rpms/qbrew.git/commit/?id=d5337fafa932add39a35656eb59319644637e110

I guess it's because upstream build system uses plain qmake directly, and Fedora's qmake no longer sets proper build flags automatically. For packages invoking qmake in their specfiles directly the fix IIRC is to switch to the %qmake_qt4 macro which sets them; maybe mimicking that is the fix here.

This bug appears to have been reported against 'rawhide' during the Fedora 26 development cycle.
Changing version to '26'.

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qbrew-0.4.1-21.fc27 has been submitted as an update to Fedora 27. https://bodhi.fedoraproject.org/updates/FEDORA-2018-a60cbf8e97

qbrew-0.4.1-21.fc28 has been submitted as an update to Fedora 28. https://bodhi.fedoraproject.org/updates/FEDORA-2018-f8cef50084

qbrew-0.4.1-21.fc27 has been pushed to the Fedora 27 testing repository. If problems still persist, please make note of it in this bug report.
See https://fedoraproject.org/wiki/QA:Updates_Testing for
instructions on how to install test updates.
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2018-a60cbf8e97

Fedora 26 changed to end-of-life (EOL) status on 2018-05-29. Fedora 26
is no longer maintained, which means that it will not receive any
further security or bug fix updates. As a result we are closing this bug.

If you can reproduce this bug against a currently maintained version of
Fedora please feel free to reopen this bug against that version. If you
are unable to reopen this bug, please file a new report against the
current release. If you experience problems, please add a comment to this
bug.

Thank you for reporting this bug and we are sorry it could not be fixed.

qbrew-0.4.1-21.fc28 has been pushed to the Fedora 28 testing repository. If problems still persist, please make note of it in this bug report.
See https://fedoraproject.org/wiki/QA:Updates_Testing for
instructions on how to install test updates.
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2018-f8cef50084

qbrew-0.4.1-21.fc27 has been pushed to the Fedora 27 stable repository. If problems still persist, please make note of it in this bug report.

qbrew-0.4.1-21.fc28 has been pushed to the Fedora 28 stable repository. If problems still persist, please make note of it in this bug report.