i965: Just assert when we flagged a compile error in the FS for now.

Dumping back to potentially 16-wide dispatch doesn't really work out
at the moment, and hopefully I'll just be able to resolve all the
failures so we never have to do this at all.

src/mesa/drivers/dri/i965/brw_fs.cpp

@@ -1871,9 +1871,6 @@ brw_wm_fs_emit(struct brw_context *brw, struct brw_wm_compile *c)
 	 ir->accept(&v);
       }
 
-      if (v.fail)
-	 return GL_FALSE;
-
       v.emit_fb_writes();
       v.assign_curb_setup();
       v.assign_urb_setup();
@@ -1882,6 +1879,11 @@ brw_wm_fs_emit(struct brw_context *brw, struct brw_wm_compile *c)
 
    v.generate_code();
 
+   assert(!v.fail); /* FINISHME: Cleanly fail, tested at link time, etc. */
+
+   if (v.fail)
+      return GL_FALSE;
+
    if (INTEL_DEBUG & DEBUG_WM) {
       const char *last_annotation_string = NULL;
       ir_instruction *last_annotation_ir = NULL;