zlib: Disable warnings to avoid changing 3rd party code

Utilities/cmzlib/CMakeLists.txt

@@ -1,5 +1,13 @@
 PROJECT(CMZLIB)
 
+# Disable warnings to avoid changing 3rd party code.
+if(CMAKE_C_COMPILER_ID MATCHES
+    "^(GNU|Clang|AppleClang|XL|VisualAge|SunPro|MIPSpro|HP|Intel)$")
+  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -w")
+elseif(CMAKE_C_COMPILER_ID STREQUAL "PathScale")
+  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -woffall")
+endif()
+
 INCLUDE_DIRECTORIES(
   "${CMZLIB_SOURCE_DIR}"
   "${CMZLIB_SOURCE_DIR}/.."