Created attachment 16904 [details]
test case

When texture's internalformat is  GL_DEPTH_COMPONENT and DEPTH_TEXTURE_MODE is GL_INTENSITY, for example:

   glTexParameteri(GL_TEXTURE_1D, GL_DEPTH_TEXTURE_MODE, GL_INTENSITY);//GL_LUMINANCE
   glTexImage1D(GL_TEXTURE_1D, 0, GL_DEPTH_COMPONENT, 2, 0,
         GL_DEPTH_COMPONENT, GL_UNSIGNED_BYTE, (void*)t);


the texture's depth value applied to RGB but not to Alpha. the pixels drawn is (t, t, t, 1), it should be (t, t, t, t).