diff options
| author | Giuseppe D'Angelo <giuseppe.dangelo@kdab.com> | 2023-09-05 09:52:31 +0200 |
|---|---|---|
| committer | Giuseppe D'Angelo <giuseppe.dangelo@kdab.com> | 2023-09-06 19:24:40 +0200 |
| commit | ca8fefca858e34bf09a7d691413fb9994e745b22 (patch) | |
| tree | 52e82d8db64abbefda7b24daaf04c11d62b0bf8b | |
| parent | 0bd1fc006097e481d8b92ee1c5246ffa1ae9379f (diff) | |
QCoreApplication::requestPermission: refactor "dead" code
An assert that checks in debug mode is morally equivalent to an
assumption/contract in release mode. Rechecking that an assumption is
true is pointless (it's true by definition), so the code for the case
the check fails is effectively "dead".
Right now Q_ASSERT(x) doesn't turn into Q_ASSUME(x) because some
compilers still have poor codegen (and basically emit a check, even in
release mode). With C++23's [[assume(x)]] we may reconsider that. As
soon as we do it, this code is no longer theoretically dead but
practically dead.
Refactor the code so that the check is done unconditionally, and
if it fails, we assert (in debug mode). In release, we protect users
from a broken backend (which may cause an endless loop of user code
re-requesting the same permission, so it's worth avoiding it).
Change-Id: If0e70e7d88a585ce16ec4838ba7be747652d8155
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>
| -rw-r--r-- | src/corelib/kernel/qcoreapplication.cpp | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/src/corelib/kernel/qcoreapplication.cpp b/src/corelib/kernel/qcoreapplication.cpp index 203f74a6666..2844da771f1 100644 --- a/src/corelib/kernel/qcoreapplication.cpp +++ b/src/corelib/kernel/qcoreapplication.cpp @@ -2921,10 +2921,11 @@ void QCoreApplication::requestPermission(const QPermission &requestedPermission, PermissionReceiver *receiver = new PermissionReceiver(std::move(slotObj), context); QPermissions::Private::requestPermission(requestedPermission, [=](Qt::PermissionStatus status) { - Q_ASSERT_X(status != Qt::PermissionStatus::Undetermined, "QPermission", - "QCoreApplication::requestPermission() should never return Undetermined"); - if (status == Qt::PermissionStatus::Undetermined) + if (status == Qt::PermissionStatus::Undetermined) { + Q_ASSERT_X(false, "QPermission", + "Internal error: requestPermission() should never return Undetermined"); status = Qt::PermissionStatus::Denied; + } if (QCoreApplication::self) { QPermission permission = requestedPermission; |