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c++valgrindglutcreatewindow

Why does Valgrind not like my usage of glutCreateWindow?

I'm using the following code...

169: const char *title = Title.c_str();
170: glutCreateWindow(title);

... Valgrind gives me the following ...

==28841== Conditional jump or move depends on uninitialised value(s)
==28841==    at 0x6FF7A4C: (within /usr/lib64/libGLcore.so.180.44)
==28841==    by 0x6FF81F7: (within /usr/lib64/libGLcore.so.180.44)
==28841==    by 0x7289B36: (within /usr/lib64/libGLcore.so.180.44)
==28841==    by 0x728A757: _nv000133gl (in /usr/lib64/libGLcore.so.180.44)
==28841==    by 0x4EAB9E9: (within /usr/lib64/libGL.so.180.44)
==28841==    by 0x4EAEA81: (within /usr/lib64/libGL.so.180.44)
==28841==    by 0x4EB1D81: (within /usr/lib64/libGL.so.180.44)
==28841==    by 0x4EA782B: glXCreateNewContext (in /usr/lib64/libGL.so.180.44)
==28841==    by 0x54DF9AA: fgOpenWindow (in /usr/lib64/libglut.so.3.8.0)
==28841==    by 0x54DE062: fgCreateWindow (in /usr/lib64/libglut.so.3.8.0)
==28841==    by 0x54DF300: glutCreateWindow (in /usr/lib64/libglut.so.3.8.0)
==28841==    by 0x4146CE: vimrid::glut::GlutApplication::Init() (GlutApplication.cpp:170)

But what is uninitialized? The title variable is initialized with the value of Title.c_str() and Title is a class member which is initialized in the constructor member initialization list...

class VimridApplication
{
    // ...

public:
    std::string Title;

    // ...
}

VimridApplication::VimridApplication() :
    Title("Untitled VimridApplication")
{
    // ...
}

class GlutApplication : public VimridApplication
{
    // ...
}
Solution

  • Valgrind comes with some default error suppression, but that probably does not cover libCLcore.

    The error-checking tools detect numerous problems in the base libraries, such as the GNU C library, and the X11 client libraries, which come pre-installed on your GNU/Linux system. You can't easily fix these, but you don't want to see these errors (and yes, there are many!) So Valgrind reads a list of errors to suppress at startup. A default suppression file is created by the ./configure script when the system is built.

    You can create your own error suppressions that you know are irrelevant to your code.