diff --git a/lib/CodeGen/Makefile b/lib/CodeGen/Makefile
index 57ee9160fcf..c235800f878 100644
--- a/lib/CodeGen/Makefile
+++ b/lib/CodeGen/Makefile
@@ -1,4 +1,4 @@
 LEVEL = ../..
-DIRS  = PreOpts InstrSelection InstrSched RegAlloc PostOpts Mapping
+PARALLEL_DIRS  = PreOpts InstrSelection InstrSched RegAlloc PostOpts Mapping
 
 include $(LEVEL)/Makefile.common
diff --git a/lib/Transforms/Makefile b/lib/Transforms/Makefile
index 31436216db4..09ae44f6107 100644
--- a/lib/Transforms/Makefile
+++ b/lib/Transforms/Makefile
@@ -1,5 +1,5 @@
 LEVEL = ../..
-DIRS = Utils Instrumentation Scalar IPO
+PARALLEL_DIRS = Utils Instrumentation Scalar IPO
 LIBRARYNAME = transforms
 BUILD_ARCHIVE = 1