Add a more reliable replacement for qt_add/removeObject().

These hooks only worked reliably with LD_PRELOAD on Linux/GCC, on other
platforms they depended on what exactly the compiler optimizer is doing
as well as some nasty assembler rewriting to actually access them. The
new system uses a simple array of function pointers that can be set to
custom hooks by tools that need this (based on ideas from Andre Poenitz).

This also covers qt_startup_hook (similar problem), and the Qt version
number that Andre had asked for.

Change-Id: I2c3e7950fd49b1b1d04176be34c2fff3293981b0
Reviewed-by: Stephen Kelly <stephen.kelly@kdab.com>
Reviewed-by: Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/src/corelib/kernel/qcoreapplication.cpp b/src/corelib/kernel/qcoreapplication.cpp
index 6868eb6a1e..7d42ffd29d 100644
--- a/src/corelib/kernel/qcoreapplication.cpp
+++ b/src/corelib/kernel/qcoreapplication.cpp
@@ -71,6 +71,7 @@
 #include <private/qfactoryloader_p.h>
 #include <private/qfunctions_p.h>
 #include <private/qlocale_p.h>
+#include <private/qhooks_p.h>
 
 #ifndef QT_NO_QOBJECT
 #if defined(Q_OS_UNIX)
@@ -765,6 +766,10 @@ void QCoreApplication::init()
 
     qt_call_pre_routines();
     qt_startup_hook();
+#ifndef QT_BOOTSTRAPPED
+    if (Q_UNLIKELY(qtHookData[QHooks::Startup]))
+        reinterpret_cast<QHooks::StartupCallback>(qtHookData[QHooks::Startup])();
+#endif
 
 #ifndef QT_NO_QOBJECT
     QCoreApplicationPrivate::is_app_running = true; // No longer starting up.