--- a/hotspot/make/linux/makefiles/buildtree.make	Wed Oct 07 15:38:37 2009 -0700
+++ b/hotspot/make/linux/makefiles/buildtree.make	Tue Oct 13 12:04:21 2009 -0700
@@ -63,20 +63,30 @@
 # For now, until the compiler is less wobbly:
 TESTFLAGS	= -Xbatch -showversion
 
-ifdef USE_SUNCC
-PLATFORM_FILE	= $(GAMMADIR)/make/$(OS_FAMILY)/platform_$(BUILDARCH).suncc
+ifeq ($(ZERO_BUILD), true)
+  PLATFORM_FILE = $(shell dirname $(shell dirname $(shell pwd)))/platform_zero
 else
-PLATFORM_FILE   = $(GAMMADIR)/make/$(OS_FAMILY)/platform_$(BUILDARCH)
+  ifdef USE_SUNCC
+    PLATFORM_FILE = $(GAMMADIR)/make/$(OS_FAMILY)/platform_$(BUILDARCH).suncc
+  else
+    PLATFORM_FILE = $(GAMMADIR)/make/$(OS_FAMILY)/platform_$(BUILDARCH)
+  endif
+endif
+
+# Allow overriding of the arch part of the directory but default
+# to BUILDARCH if nothing is specified
+ifeq ($(VARIANTARCH),)
+  VARIANTARCH=$(BUILDARCH)
 endif
 
 ifdef FORCE_TIERED
 ifeq		($(VARIANT),tiered)
-PLATFORM_DIR	= $(OS_FAMILY)_$(BUILDARCH)_compiler2
+PLATFORM_DIR	= $(OS_FAMILY)_$(VARIANTARCH)_compiler2
 else
-PLATFORM_DIR	= $(OS_FAMILY)_$(BUILDARCH)_$(VARIANT)
+PLATFORM_DIR	= $(OS_FAMILY)_$(VARIANTARCH)_$(VARIANT)
 endif
 else
-PLATFORM_DIR    = $(OS_FAMILY)_$(BUILDARCH)_$(VARIANT)
+PLATFORM_DIR    = $(OS_FAMILY)_$(VARIANTARCH)_$(VARIANT)
 endif
 
 #
@@ -321,6 +331,7 @@
 DATA_MODE/sparcv9 = 64
 DATA_MODE/amd64   = 64
 DATA_MODE/ia64    = 64
+DATA_MODE/zero    = $(ARCH_DATA_MODEL)
 
 JAVA_FLAG/32 = -d32
 JAVA_FLAG/64 = -d64