diff --git a/include/llvm/Config/config.h.cmake b/include/llvm/Config/config.h.cmake
index 408c590bebb..97af6955d9e 100644
--- a/include/llvm/Config/config.h.cmake
+++ b/include/llvm/Config/config.h.cmake
@@ -230,6 +230,9 @@
 /* Define to 1 if you have the `udis86' library (-ludis86). */
 #undef HAVE_LIBUDIS86
 
+/* Define to 1 if you have the 'z' library (-lz). */
+#cmakedefine HAVE_LIBZ ${HAVE_LIBZ}
+
 /* Define to 1 if you have the <limits.h> header file. */
 #cmakedefine HAVE_LIMITS_H ${HAVE_LIMITS_H}
 
diff --git a/lib/Support/Compression.cpp b/lib/Support/Compression.cpp
index d0adf79ec78..497b17ec92b 100644
--- a/lib/Support/Compression.cpp
+++ b/lib/Support/Compression.cpp
@@ -23,7 +23,7 @@
 
 using namespace llvm;
 
-#if LLVM_ENABLE_ZLIB == 1
+#if LLVM_ENABLE_ZLIB == 1 && HAVE_LIBZ
 static int encodeZlibCompressionLevel(zlib::CompressionLevel Level) {
   switch (Level) {
     case zlib::NoCompression: return 0;
diff --git a/unittests/Support/CompressionTest.cpp b/unittests/Support/CompressionTest.cpp
index aad7ed0e89a..c8e2cd9f02b 100644
--- a/unittests/Support/CompressionTest.cpp
+++ b/unittests/Support/CompressionTest.cpp
@@ -22,7 +22,7 @@ using namespace llvm;
 
 namespace {
 
-#if LLVM_ENABLE_ZLIB == 1
+#if LLVM_ENABLE_ZLIB == 1 && HAVE_LIBZ
 
 void TestZlibCompression(StringRef Input, zlib::CompressionLevel Level) {
   OwningPtr<MemoryBuffer> Compressed;