r300: Fix scons build.
diff --git a/.gitignore b/.gitignore
index 1c3d446..f43ff37 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,6 +4,7 @@
 *.ilk
 *.o
 *.obj
+*.os
 *.pc
 *.pdb
 *.pyc