diff --git a/llvm/projects/Makefile b/llvm/projects/Makefile
index 491d596eca9a..1318a35d941e 100644
--- a/llvm/projects/Makefile
+++ b/llvm/projects/Makefile
@@ -14,9 +14,12 @@ include $(LEVEL)/Makefile.config
 # Before 2008.06.24 it lived in llvm-test, so exclude that as well for now.
 DIRS:= $(filter-out llvm-test test-suite,$(patsubst $(PROJ_SRC_DIR)/%/Makefile,%,$(wildcard $(PROJ_SRC_DIR)/*/Makefile)))
 
-# Don't build compiler-rt either, it isn't designed to be built directly.
+# Don't build compiler-rt, it isn't designed to be built directly.
 DIRS := $(filter-out compiler-rt,$(DIRS))
 
+# Don't build libcxx, it isn't designed to be built directly.
+DIRS := $(filter-out libcxx,$(DIRS))
+
 # Sparc cannot link shared libraries (libtool problem?)
 ifeq ($(ARCH), Sparc)
 DIRS := $(filter-out sample, $(DIRS))