Comment 1 for bug 1173355

In fact the crash is a failed assertion which appears in debug mode.

By commenting out this assertion, there are then three other failed assertions at StelSphereGeometry.cpp:373
      Q_ASSERT(fabs(vertices->a.length()-1.)<0.00001);
      Q_ASSERT(fabs(vertices->b.length()-1.)<0.00001);
      Q_ASSERT(fabs(vertices->c.length()-1.)<0.00001);

By commenting them out, the code does not crash but the spherical cap is not correctly drawn and the program eventually crashes (except in gdb and valgrind)
(nb: there's a mistake in the code sample I gave, the alpha channel should be 1 to see something, and it's better to set a small aperture to the spherical cap)

Under valgrind the spherical cap is correctly drawn and the program does not crash, but there are many "Invalid read" errors from freed memory blocks.

Few weeks ago everything worked with basically the same code. Since then I upgraded graphics card drivers. That's the only thing I can think of but I don't understand how it could explain these new issues.