Index: lldb/trunk/lit/CMakeLists.txt
===================================================================
--- lldb/trunk/lit/CMakeLists.txt
+++ lldb/trunk/lit/CMakeLists.txt
@@ -11,6 +11,10 @@
   set(ENABLE_SHARED 0)
 endif(BUILD_SHARED_LIBS)
 
+# the value is not canonicalized within LLVM
+llvm_canonicalize_cmake_booleans(
+  LLVM_ENABLE_ZLIB)
+
 configure_lit_site_cfg(
   ${CMAKE_CURRENT_SOURCE_DIR}/lit.site.cfg.in
   ${CMAKE_CURRENT_BINARY_DIR}/lit.site.cfg)
Index: lldb/trunk/lit/lit.site.cfg.in
===================================================================
--- lldb/trunk/lit/lit.site.cfg.in
+++ lldb/trunk/lit/lit.site.cfg.in
@@ -12,7 +12,7 @@
 config.python_executable = "@PYTHON_EXECUTABLE@"
 config.cc = "@LLDB_TEST_C_COMPILER@"
 config.cxx = "@LLDB_TEST_CXX_COMPILER@"
-config.have_zlib = @HAVE_LIBZ@
+config.have_zlib = @LLVM_ENABLE_ZLIB@
 
 # Support substitution of the tools and libs dirs with user parameters. This is
 # used when we can't determine the tool dir at configuration time.