Failure in debug build

[kegon]

I have an application that seems to work OK in release mode; when I build in debug mode I get a segmentation fault. It looks like a Qt bug to me, does anyone have some tips for how I should proceed ?

Running in gdb:

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Program received signal SIGSEGV, Segmentation fault.
__strlen_sse42 () at ../sysdeps/x86_64/multiarch/strlen-sse4.S:32
32 ../sysdeps/x86_64/multiarch/strlen-sse4.S: No such file or directory.
(gdb) bt
#0 __strlen_sse42 () at ../sysdeps/x86_64/multiarch/strlen-sse4.S:32
#1 0x00007ffff2ea958c in QCoreApplication::arguments() ()
from /home/developer00/Source/Qt/5.3/gcc_64/lib/libQt5Core.so.5
#2 0x00007fffeab1bfc3 in ?? ()
from /home/developer00/Source/Qt/5.3/gcc_64/plugins/platforms/libqxcb.so
#3 0x00007fffeab1c3a9 in ?? ()
from /home/developer00/Source/Qt/5.3/gcc_64/plugins/platforms/libqxcb.so
#4 0x00007fffeab28c8d in ?? ()
from /home/developer00/Source/Qt/5.3/gcc_64/plugins/platforms/libqxcb.so
#5 0x00007fffeab1bdb9 in ?? ()
from /home/developer00/Source/Qt/5.3/gcc_64/plugins/platforms/libqxcb.so
#6 0x00007ffff33f5d23 in QWindow::create() ()
from /home/developer00/Source/Qt/5.3/gcc_64/lib/libQt5Gui.so.5
#7 0x00007ffff4857df1 in QGLContext::chooseContext(QGLContext const*) () from /home/developer00/Source/Qt/5.3/gcc_64/lib/libQt5OpenGL.so.5
#8 0x00007ffff482f599 in QGLContext::create(QGLContext const*) ()
from /home/developer00/Source/Qt/5.3/gcc_64/lib/libQt5OpenGL.so.5
#9 0x00007ffff4857757 in QGLWidget::setContext(QGLContext*, QGLContext const*, bool) ()
from /home/developer00/Source/Qt/5.3/gcc_64/lib/libQt5OpenGL.so.5
#10 0x00007ffff4834bba in QGLWidgetPrivate::initContext(QGLContext*, QGLWidget const*) ()
from /home/developer00/Source/Qt/5.3/gcc_64/lib/libQt5OpenGL.so.5
#11 0x000000000050f3cb in MyWidget::MyWidget (this=
0x7fffe41b8250, parent=0x0, form=...) at mywidget.cc:24
#12 0x000000000043cfa6 in MyApp::MyApp (this=
0x7fffe4026340, app_dir_path=..., parent=0x0, flags=...)
at myapp.cc:198
#13 0x000000000043bf47 in main (argc=1, argv=0x7fffffffe188)
at main.cc:78
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It looks like constructing MyWidget is the root of the problem, that line is
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MyWidget::MyWidget(QWidget *parent, QGLFormat &form) : QGLWidget(form, parent)
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Which looks OK to me.

If I run in valgrind I get

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ASSERT: "uint(i) < uint(size())" in file /home/developer00/Source/Qt/5.3/gcc_64/include/QtCore/qstring.h, line 790
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