diff --git a/src/gui/sdlmain.cpp b/src/gui/sdlmain.cpp
index ad1d427b..84b8be4f 100644
--- a/src/gui/sdlmain.cpp
+++ b/src/gui/sdlmain.cpp
@@ -1313,9 +1313,9 @@ static void GUI_StartUp(Section * sec) {
 	glUnmapBufferARB = (PFNGLUNMAPBUFFERARBPROC)SDL_GL_GetProcAddress("glUnmapBufferARB");
 	const char * gl_ext = (const char *)glGetString (GL_EXTENSIONS);
 	if(gl_ext && *gl_ext){
-		sdl.opengl.packed_pixel=(strstr(gl_ext,"EXT_packed_pixels") > 0);
-		sdl.opengl.paletted_texture=(strstr(gl_ext,"EXT_paletted_texture") > 0);
-		sdl.opengl.pixel_buffer_object=(strstr(gl_ext,"GL_ARB_pixel_buffer_object") >0 ) &&
+		sdl.opengl.packed_pixel=(strstr(gl_ext,"EXT_packed_pixels") != NULL);
+		sdl.opengl.paletted_texture=(strstr(gl_ext,"EXT_paletted_texture") != NULL);
+		sdl.opengl.pixel_buffer_object=(strstr(gl_ext,"GL_ARB_pixel_buffer_object") != NULL ) &&
 		    glGenBuffersARB && glBindBufferARB && glDeleteBuffersARB && glBufferDataARB &&
 		    glMapBufferARB && glUnmapBufferARB;
     	} else {