--- a/hotspot/make/windows/makefiles/product.make	Thu Dec 02 14:00:03 2010 -0500
+++ b/hotspot/make/windows/makefiles/product.make	Wed Dec 01 15:04:06 2010 +0100
@@ -27,7 +27,12 @@
 AOUT=$(HS_FNAME)
 GENERATED=../generated
 
-default:: _build_pch_file.obj $(AOUT) checkAndBuildSA
+# Allow the user to turn off precompiled headers from the command line.
+!if "$(USE_PRECOMPILED_HEADER)" != "0"
+BUILD_PCH_FILE=_build_pch_file.obj
+!endif
+
+default:: $(BUILD_PCH_FILE) $(AOUT) checkAndBuildSA
 
 !include ../local.make
 !include compile.make