Both whenAll() and whenAny() have two overloads:
* an overload taking two input iterators, e.g.
whenAll(IntpuIt begin, InputIt end)
* an overload taking an arbitrary number of future objects, e.g.
whenAll(Futures &&... futures)
The public APIs are properly constrained, but internally they call
QtPrivate::when*Impl() template functions, that have the same two
overloads, but do not have any constraints.
As a result, passing exactly two QFuture<T>{} objects was leading to
the compiler picking the Impl overload that takes a pair of iterators.
Fix it by applying a subset of constraints from the public API to
the private implementation as well.
Amends 102f7d31c4 which was introduced
for Qt 6.3, so picking down to Qt 6.5.
Fixes: QTBUG-131959
Pick-to: 6.5
Change-Id: Ide29ac9a494d07870e92957c40c1f614e56825f8
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
(cherry picked from commit 8aef5b0d8fd57684abe39c88af8c14d8882ef07b)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
(cherry picked from commit 90fab1e4e98962ecaff5fd66d218d4f76cb7b8cd)
6355568cc0