AMD: imageStore stops working after using glTexImage2D to resize GL_R32UI texture

I'm encountering a problem using glTexImage2D with data = nullptr to resize an integer texture.

The first call to glTexImage2D allocates the texture just fine. When I call it again with a different size, it "succeeds" in resizing, as reported by glGetTexLevelParamer. However, when I attempt to write to the texture with imageStore, nothing gets written.

I can clear the texture just fine, and reading it gives me back the cleared value.

The texture isn't bound to any active framebuffer when I use imageStore, and imageStore worked before calling TexImage2D for the second time.

Neither glGetError nor ARB_debug_output report any errors.

Test case reproducing the bug: https://gist.github.com/anonymous/7819317