st/wgl: add null pointer check for HUD texture

Fixes crash when using HUD with Nobel Clinician Viewer.

Reviewed-by: Jose Fonseca <jfonseca@vmware.com>

diff --git a/src/gallium/state_trackers/wgl/stw_framebuffer.c b/src/gallium/state_trackers/wgl/stw_framebuffer.c
index fbe77b23d9c05d846ec18e88d0607074ef5f2435..11f60b6c763172d046eb4bfd655ada080fd6e4d7 100644 (file)
--- a/src/gallium/state_trackers/wgl/stw_framebuffer.c
+++ b/src/gallium/state_trackers/wgl/stw_framebuffer.c
@@ -611,7 +611,9 @@ DrvSwapBuffers(HDC hdc)
          /* Display the HUD */
          struct pipe_resource *back =
             stw_get_framebuffer_resource(fb->stfb, ST_ATTACHMENT_BACK_LEFT);
-         hud_draw(ctx->hud, back);
+         if (back) {
+            hud_draw(ctx->hud, back);
+         }
       }
 
       if (ctx->current_framebuffer == fb) {