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        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - Segfault in glGetActiveUniformName"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=86594">86594</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>Segfault in glGetActiveUniformName
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>Mesa
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>10.3
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>x86-64 (AMD64)
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>Linux (All)
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>major
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>medium
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>Mesa core
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>mesa-dev@lists.freedesktop.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>simon@gimp.org
          </td>
        </tr></table>
      <p>
        <div>
        <pre>I am trying to get some information about a compiled GL shader program, in
particular I need to get information about the Uniform Variables used.

The code I use is this:

  glGetProgramiv (program, GL_ACTIVE_UNIFORMS, &n_uniforms);
  fprintf (stderr, "%d uniforms:\n", n_uniforms);

  for (i = 0; i < n_uniforms; i++)
    {
      glGetActiveUniformName (program, i, 79, &namelen, name);
      name[namelen] = '\0';
      fprintf (stderr, "  %2d: %s\n", i, name);
    }

I get a segfault within glGetActiveUniformName, something is wrong here. The
same code works fine with the NVidia proprietary drivers.

Some more information:

GL_VERSION   : 2.1 Mesa 10.3.2
GL_VENDOR    : Intel Open Source Technology Center
GL_RENDERER  : Mesa DRI Intel(R) Ironlake Mobile 
GLEW_VERSION : 1.10.0
GLSL VERSION : 1.20

This is using debian unstable with libgl1-mesa-glx:amd64, 10.3.2-1, amd64

Valgrind is not really helpful, even with debug symbols installed:

==27042== Process terminating with default action of signal 11 (SIGSEGV)
==27042==  Bad permissions for mapped region at address 0x0
==27042==    at 0x0: ???
==27042==    by 0x402BFF: main (shadertoy.c:458)
==27042==</pre>
        </div>
      </p>
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