[plt-scheme] compiler/compiler vs mzc

I'm getting different results of generated bytecode between using the
compiler/compiler collection and mzc.  I believe the distinguishing
feature is that I'm using compiler/compiler through DrScheme.  For
example, when compiling:



dyoo at mithril:~/work/mzscheme-vm/tests/42$ cat 42.ss
#lang scheme/base
42



Under vanilla mzc, I'm getting the following:

dyoo at mithril:~/work/mzscheme-vm/tests/42/compiled$ ls
42_ss.dep  42_ss.zo
dyoo at mithril:~/work/mzscheme-vm/tests/42/compiled$ mzscheme
Welcome to MzScheme v4.2.5 [3m], Copyright (c) 2004-2010 PLT Scheme Inc.
> (require compiler/zo-parse)
> (zo-parse (open-input-file "42_ss.zo"))
#(struct:compilation-top
  0
  #(struct:prefix 0 (#f) ())
  #(struct:mod
    |42|
    #<module-path-index>
    #(struct:prefix
      0
      (#(struct:module-variable #<module-path-index> print-values 0 0))
      ())
    ()
    ((0 #<module-path-index>) (1) (-1) (#f))
    (#(struct:apply-values #(struct:toplevel 0 0 #f #f) 42))
    ()
    (() () ())
    0
    #(struct:toplevel 0 0 #f #f)
    #(scheme/base/lang/reader get-info-getter (scheme/base #f))
    #t))




But under compiler/compiler, I'm getting a different bytecode
structure which appears to introduce tracing and other debugging
stuff:

dyoo at mithril:~/work/mzscheme-vm/tests/42/compiled-test$ ls
42_ss_merged_ss.zo  42_ss.zo
dyoo at mithril:~/work/mzscheme-vm/tests/42/compiled-test$ mzscheme
Welcome to MzScheme v4.2.5 [3m], Copyright (c) 2004-2010 PLT Scheme Inc.
> (require compiler/zo-parse)
> (zo-parse (open-input-file "42_ss.zo"))
#(struct:compilation-top
  0
  #(struct:prefix 0 (#f) ())
  #(struct:mod
    |42|
    #<module-path-index>
    #(struct:prefix
      0
      (#(struct:module-variable #<module-path-index> init-test-coverage 1 0)
       #(struct:module-variable #<module-path-index> errortrace-key 0 0)
       #(struct:module-variable #<module-path-index> print-values 0 0))
      ())
    ()
    ((0 #<module-path-index> #<module-path-index>)
     (1 #<module-path-index>)
     (-1)
     (#f))
    (#(struct:application #(struct:toplevel 1 0 #f #f) (()))
     #(struct:with-cont-mark
       #(struct:toplevel 0 1 #f #f)
       ((call-with-values (lambda () '42) print-values)
        "../tests/42/42.ss"
        2
        0
        19
        2)
       #(struct:apply-values #(struct:toplevel 0 2 #f #f) 42)))
    ()
    (() () ())
    1
    #(struct:toplevel 0 0 #f #f)
    #f
    #(struct:stx
      #(struct:wrapped
        #f
        (#(struct:module-rename
           0
           normal
           935326
           (#(struct:all-from-module #<module-path-index> 0 0 () #f)
            #(struct:all-from-module #<module-path-index> 0 0 () #f))
           ()
           ()
           #f)
         #(struct:module-rename
           0
           normal
           935326
           (#(struct:all-from-module #<module-path-index> 0 0 () #f)
            #(struct:all-from-module #<module-path-index> 0 0 () #f))
           ()
           ()
           #f)
         #(struct:module-rename
           0
           normal
           935326
           (#(struct:all-from-module #<module-path-index> 0 0 () #f)
            #(struct:all-from-module #<module-path-index> 0 0 () #f))
           ()
           ()
           #f)
         #(struct:module-rename
           0
           normal
           935326
           (#(struct:all-from-module #<module-path-index> 0 0 () #f)
            #(struct:all-from-module #<module-path-index> 0 0 () #f))
           ()
           ()
           #f))
        #f))))





What I do to reset the compiler/compiler collection so that it has
identical behavior to mzc?