Mesa (mesa_7_6_branch): st/mesa: Check for single level mipmap trees.

[Younes Manton]

Module: Mesa
Branch: mesa_7_6_branch
Commit: ace937f1651c64d7fb22917489e29761130aaa0d
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=ace937f1651c64d7fb22917489e29761130aaa0d

Author: Younes Manton <younes.m at gmail.com>
Date:   Sun Dec 20 20:11:55 2009 -0500

st/mesa: Check for single level mipmap trees.

The assert in util_gen_mipmap() caught it, although
it does the right thing anyway.

---

 src/mesa/state_tracker/st_gen_mipmap.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/src/mesa/state_tracker/st_gen_mipmap.c b/src/mesa/state_tracker/st_gen_mipmap.c
index f75b234..c3bea31 100644
--- a/src/mesa/state_tracker/st_gen_mipmap.c
+++ b/src/mesa/state_tracker/st_gen_mipmap.c
@@ -215,6 +215,9 @@ st_generate_mipmap(GLcontext *ctx, GLenum target,
    /* find expected last mipmap level */
    lastLevel = compute_num_levels(ctx, texObj, target) - 1;
 
+   if (lastLevel == 0)
+      return;
+
    if (pt->last_level < lastLevel) {
       /* The current gallium texture doesn't have space for all the
        * mipmap levels we need to generate.  So allocate a new texture.