diff --git a/runtime/Makefile b/runtime/Makefile
index 8398c1f8122..c84ada158a6 100644
--- a/runtime/Makefile
+++ b/runtime/Makefile
@@ -12,7 +12,7 @@ LEVEL = ..
 include $(LEVEL)/Makefile.config
 
 ifneq ($(wildcard $(LLVMGCCDIR)),)
-PARALLEL_DIRS  := GCCLibraries  libdummy  libprofile  libtrace libpng zlib
+PARALLEL_DIRS  := GCCLibraries  libdummy  libprofile  libtrace 
 else
 PARALLEL_DIRS  := 
 install all ::