diff --git a/runtime/zlib/Makefile b/runtime/zlib/Makefile
index ca08ff9b45f..f9822d5c293 100644
--- a/runtime/zlib/Makefile
+++ b/runtime/zlib/Makefile
@@ -11,6 +11,7 @@ BYTECODE_LIBRARY=1
 BUILD_ARCHIVE=1
 DONT_BUILD_RELINKED=1
 LIBRARYNAME=z
+CPPFLAGS += -DNO_DUMMY_DECL=1
 
 Source = adler32.c compress.c crc32.c gzio.c uncompr.c deflate.c trees.c \
          zutil.c inflate.c infback.c inftrees.c inffast.c