[qt/qt/qtbase]: Summary of bulk changes made

Git repository change summary for qt/qt/qtbase
Pushed by mirror-service into branch '6.12'.
Changed from 28c91df6f76b9568c3b587acf9264d4f5c798cc8 to 499bffa4b9f6dc92dccfc5c3092c4ef6ddb1536d
Acknowledgement was received that this change introduces only existing code that has been pushed to another public open source repository.

This change contains the following new commits:

Git commit 8d24b73dbfd67790dfc2f3482b204ddeeeb8a9a0 by Qt Cherry-pick Bot (on behalf of Edward Welbourne) on 29/07/2026 at 16:54..
Fix some \deprecated docs to end in sentence-terminators

This is in preparation of an upcoming qdoc change that will turn
missing terminators into a warning, which would exceed configured
warning limits in qtbase.

Pick-to: 6.11 6.8 6.5
Change-Id: Ibdaf2bd617fd24d808956b2322be26b8e1bcda1c
Reviewed-by: Marc Mutz <[email protected]>
(cherry picked from commit a286b5cf5dca804983d1cb3dc8281d4f80029fc5)
Reviewed-by: Qt Cherry-pick Bot <[email protected]>
https://invent.kde.org/qt/qt/qtbase/-/commit/8d24b73dbfd67790dfc2f3482b204ddeeeb8a9a0

Git commit 91c94492b8eb7e52604df148a4d68f36a7d8d820 by Qt Cherry-pick Bot (on behalf of Edward Welbourne) on 29/07/2026 at 16:54..
Avoid overflow in QJalaliCalendar::dateToJulianDay()

If year is close to INT_MIN, subtracting 474 from it will underflow.
However, all we need is the quotient and remainder of the result of
that subtraction, which we can obtain without overflow by rearranging
the arithmetic. Credit to OSS-Fuzz (issue 522858568) for finding it.

The computation of c = qDiv<cycleYears>(y); and then subtracting c *
cycleYears from y was equivalent to computing qDivMod<cycleYears>(y)
and using its quotient and remainder. As y is just year minus an
offset, we can qDivMod<cycleYears>(year) directly and then adjust its
result by the relevant offset, transfering cycleYears from quotient to
remainder first if remainder was too low. Since the quotient's range
of possible values is well within that of int (by a factor of
cycleYears) its adjustment is in no danger of underflow; and
remainder's range is likewise safely in the range from zero to (just
before) cycleYears, so safe.

Add tests of QDateTime and the new temporal parser based on the fuzzer
test-data for the former that found this. The latter made the failure
reachable by supporting years with more than 4 digits, and is new in
6.12, so these tests won't work in older versions, but the overflow
fix is still valid there.

Pick-to: 6.11 6.8
Fixes: QTBUG-147419
Change-Id: Id9f7ce3d7bfa1b7c671a41fdbe9edcc236f17e58
Reviewed-by: Mate Barany <[email protected]>
(cherry picked from commit 708074532841fd16291e69eedc016fb106c8d3a6)
Reviewed-by: Qt Cherry-pick Bot <[email protected]>
https://invent.kde.org/qt/qt/qtbase/-/commit/91c94492b8eb7e52604df148a4d68f36a7d8d820

Git commit c889015604dd9159d77cbd85f5ecdb6176d35010 by Qt Cherry-pick Bot (on behalf of Edward Welbourne) on 29/07/2026 at 16:54..
Align parsing of time-zone long forms with old parser

Amends commit 0923c473e20d66e0fb5e12a5fef7683bd979d120 (6.12).
I'd failed to notice that the old parser accepted the LocalTime name
supplied by the system (from tzname[] or equivalent) for the
full-length tttt zone format as well as the generic t format.
Tweak the parsing of the old Qt format strings to take that into
account.

Thanks to Albert Astals Cid for catching this with a KDE test.

Change-Id: I701addce6ffdf8b0e96e5b90042fe0549d666702
Reviewed-by: Mate Barany <[email protected]>
(cherry picked from commit 794dd25f82aad26395b65b8ddc0fd596cbf04fd3)
Reviewed-by: Qt Cherry-pick Bot <[email protected]>
https://invent.kde.org/qt/qt/qtbase/-/commit/c889015604dd9159d77cbd85f5ecdb6176d35010

Git commit 24c69df4161af14c233714f3f87f9a044f55fb75 by Qt Cherry-pick Bot (on behalf of Edward Welbourne) on 29/07/2026 at 16:54..
Simplify tst_QtParseTimeZone::prefix_data() with another lambda

For most zones tested, I'd followed a common pattern that could
sensibly be expressed (as Thiago pointed out in review) as a lambda
wrapping the zoneTests() one.

Task-number: QTBUG-77948
Change-Id: I67f4079dbaff70a5558dedf813792820b3b13ce8
Reviewed-by: Mate Barany <[email protected]>
(cherry picked from commit e14f178a47fe7c6d3f932d0dce535138718cee45)
Reviewed-by: Qt Cherry-pick Bot <[email protected]>
https://invent.kde.org/qt/qt/qtbase/-/commit/24c69df4161af14c233714f3f87f9a044f55fb75

Git commit 499bffa4b9f6dc92dccfc5c3092c4ef6ddb1536d by Qt Cherry-pick Bot (on behalf of Edward Welbourne) on 29/07/2026 at 16:55..
Replace IANA ID size constraint magic numbers with named constants

In the process rename one local variable, and change its start value,
to match the semantics of the natural name for its limit.

Task-number: QTBUG-77948
Change-Id: I4ae1d47b2b0741cd313b8b5d70228082dbf273b3
Reviewed-by: Mate Barany <[email protected]>
(cherry picked from commit 37bf3f6aa6a9a7404ac27187245907dd0e7f1882)
Reviewed-by: Qt Cherry-pick Bot <[email protected]>
https://invent.kde.org/qt/qt/qtbase/-/commit/499bffa4b9f6dc92dccfc5c3092c4ef6ddb1536d