diff --git a/tools/comcom.lisp b/tools/comcom.lisp
index 2c8b09836799290ef44422023b4c9069f8fdc18f..6994c0cd9e34988837350d9f4963812500a5850b 100644
--- a/tools/comcom.lisp
+++ b/tools/comcom.lisp
@@ -40,11 +40,12 @@
 (defvar c::*target-backend* (c::make-backend))
 
 (when (string= (old-c:backend-name old-c:*backend*) "PMAX")
-  (comf "target:compiler/mips/parms" :proceed t)
-  (comf "target:compiler/generic/objdef" :proceed t))
+  (comf "target:compiler/mips/parms" :proceed t))
 (when (string= (old-c:backend-name old-c:*backend*) "SPARC")
-  (comf "target:compiler/sparc/parms" :proceed t)
-  (comf "target:compiler/generic/objdef" :proceed t))
+  (comf "target:compiler/sparc/parms" :proceed t))
+(when (string= (old-c:backend-name old-c:*backend*) "RT")
+  (comf "target:compiler/rt/params" :proceed t))
+(comf "target:compiler/generic/objdef" :proceed t)
 
 (comf "target:code/struct") ; For defstruct description structures.
 (comf "target:compiler/proclaim") ; For COOKIE structure.
@@ -164,6 +165,37 @@
   (comf "target:assembly/sparc/arith")
   (comf "target:assembly/sparc/alloc"))
 
+(when (string= (old-c:backend-name old-c:*backend*) "RT")
+  (comf "target:compiler/rt/insts")
+  (comf "target:compiler/rt/macros" :load *load-stuff*)
+  (comf "target:compiler/rt/vm")
+  (comf "target:compiler/rt/move")
+  (comf "target:compiler/rt/sap")
+  (comf "target:compiler/rt/system")
+  (comf "target:compiler/rt/char")
+  (comf "target:compiler/rt/float")
+  (comf "target:compiler/rt/memory")
+  (comf "target:compiler/rt/static-fn")
+  (comf "target:compiler/rt/arith")
+  (comf "target:compiler/rt/subprim")
+  (comf "target:compiler/rt/debug")
+  (comf "target:compiler/rt/c-call")
+  (comf "target:compiler/rt/cell")
+  (comf "target:compiler/rt/values")
+  (comf "target:compiler/rt/alloc")
+  (comf "target:compiler/rt/call")
+  (comf "target:compiler/rt/nlx")
+  (comf "target:compiler/rt/print")
+  (comf "target:compiler/rt/array")
+  (comf "target:compiler/rt/pred")
+  (comf "target:compiler/rt/type-vops")
+
+  (comf "target:assembly/rt/support" :load *load-stuff*)
+  (comf "target:assembly/rt/assem-rtns")
+  (comf "target:assembly/rt/array")
+  (comf "target:assembly/rt/arith")
+  (comf "target:assembly/rt/alloc"))
+
 (comf "target:compiler/pseudo-vops")
 
 ); with-compilation-unit for back end.