diff --git a/util/test/demos/gl/gl_queries_in_use.cpp b/util/test/demos/gl/gl_queries_in_use.cpp
index fa58cabad..8a3d3a926 100644
--- a/util/test/demos/gl/gl_queries_in_use.cpp
+++ b/util/test/demos/gl/gl_queries_in_use.cpp
@@ -65,7 +65,7 @@ RD_TEST(GL_Queries_In_Use, OpenGLGraphicsTest)
     glAttachShader(program, vs);
     glAttachShader(program, fs);
 
-    GLchar *posOnly = "gl_Position";
+    const GLchar *posOnly = "gl_Position";
     glTransformFeedbackVaryings(program, 1, &posOnly, GL_INTERLEAVED_ATTRIBS);
 
     glLinkProgram(program);