GCC says that CaseConversion::Upper is ambiguous between - struct QUnicodeTables::CaseConversion - enum class QtIcuPrivate::CaseConversion In a -unity-build, those two entities are in-scope at the same time, so disambiguate by renaming the entity with narrower scope. The alternative, fully qualifying the enum uses with the QtIcuPrivate namespace would have caused similar churn, and would have run the risk of being removed again by the mythical maintenance programmer, due to use of "using namespace QtIcuPrivate;" in at least some of the functions that refer to the enum. Amends eaf77edebdf1c0b1682c28c014f2d81479af0051, which added the conflicting QUnicodeTables::CaseConversion and/or 6f4d64b21ec90a792c7c8308a6615ca87b9ea6eb, which added QtIcuPrivate::CaseConversion, which this patch changes now. Pick-to: 6.10 6.8 6.5 Task-number: QTBUG-109394 Change-Id: I1f6379a200ae0cea5befd5d6cf210be14c0344f0 Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>