diff --git a/AMBuildScript b/AMBuildScript
index 2b7226c..08880be 100644
--- a/AMBuildScript
+++ b/AMBuildScript
@@ -181,7 +181,7 @@ class MMSConfig(object):
       if cxx.behavior == 'gcc':
         cfg.cflags += ['-O3']
       elif cxx.behavior == 'msvc':
-        cfg.cflags += ['/Ox']
+        cfg.cflags += ['/Ox', '/Zo']
         cfg.linkflags += ['/OPT:ICF', '/OPT:REF']
 
     # Debugging
@@ -190,7 +190,7 @@ class MMSConfig(object):
       if cxx.behavior == 'gcc':
         cfg.cflags += ['-g3']
       elif cxx.behavior == 'msvc':
-        cfg.cflags += ['/Od', '/Zo', '/RTC1']
+        cfg.cflags += ['/Od', '/RTC1']
 
     # This needs to be after our optimization flags which could otherwise disable it.
     if cxx.name == 'msvc':