diff --git a/tools/comcom.lisp b/tools/comcom.lisp
index e4039c6cb01beb79e48c8f057e281c2c7f874b11..b348022e3c845d67a93d22d0a171dbe17a58d279 100644
--- a/tools/comcom.lisp
+++ b/tools/comcom.lisp
@@ -225,7 +225,9 @@
     (:optimize '(optimize (debug-info 2) (safety 1)))
   (comf "target:compiler/pack"))
 (comf "target:compiler/codegen")
-(comf "target:compiler/debug")
+(with-compilation-unit
+    (:optimize '(optimize (debug-info 2) (safety 2)))
+  (comf "target:compiler/debug"))
 (comf "target:compiler/assem-check")
 (comf "target:compiler/statcount")
 (comf "target:compiler/dyncount")