Bug#635724: vlc: FTBFS (kfreebsd-i386) Segmentation fault (core dumped) ../bin/vlc-cache-gen .

[Reinhard Tartler]

On Wed, Aug 03, 2011 at 13:35:55 (CEST), Reinhard Tartler wrote:

[...]

> Not sure what is the right thing to do here. Maybe there was indeed
> recently some change in the toolchain, as Petr suggests, that affects
> the order of execution of global destructors and causes this
> segfault. OTOH, maybe the function registeredInterpolators should just
> return if registeredInterpolators() returns a 0 pointer.

By sheer luck, I found this in google's results: http://pastebin.com/W38uFJEQ

In case it vanishes, here is a copy of the contents of the paste:

>From 3031f1b1ebafe6dfdb99b4a745cac3f0887a8006 Mon Sep 17 00:00:00 2001
From: Thiago Macieira <thiago.macieira at nokia.com>
Date: Wed, 26 Jan 2011 14:06:11 +0100
Subject: [PATCH] Check if the interpolators have already been deleted.

During application destruction, the order in which static destructors
is run is undetermined. So avoid a null-pointer dereference.

Task-number: QTBUG-16855
Reviewed-by: pending
---
 src/corelib/animation/qvariantanimation.cpp |   13 +++++++++----
 1 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/src/corelib/animation/qvariantanimation.cpp b/src/corelib/animation/qvariantanimation.cpp
index 212e85d..c76cb89 100644
--- a/src/corelib/animation/qvariantanimation.cpp
+++ b/src/corelib/animation/qvariantanimation.cpp
@@ -431,12 +431,17 @@ void QVariantAnimation::registerInterpolator(QVariantAnimation::Interpolator fun
 {
     // will override any existing interpolators
     QInterpolatorVector *interpolators = registeredInterpolators();
+    // When built on solaris with GCC, the destructors can be called
+    // in such an order that we get here with interpolators == NULL,
+    // to continue causes the app to crash on exit with a SEGV
+    if (interpolators) {
 #ifndef QT_NO_THREAD
-    QMutexLocker locker(QMutexPool::globalInstanceGet(interpolators));
+        QMutexLocker locker(QMutexPool::globalInstanceGet(interpolators));
 #endif
-    if (int(interpolationType) >= interpolators->count())
-        interpolators->resize(int(interpolationType) + 1);
-    interpolators->replace(interpolationType, func);
+        if (int(interpolationType) >= interpolators->count())
+            interpolators->resize(int(interpolationType) + 1);
+        interpolators->replace(interpolationType, func);
+    }
 }
 
 
-- 
1.7.3.2.431.ge2f5c


Qt4 Maintainers, can you perhaps check if this patch has been
approved or even incorporated upstream?

-- 
Gruesse/greetings,
Reinhard Tartler, KeyID 945348A4