Index: CMakeLists.txt
===================================================================
--- CMakeLists.txt
+++ CMakeLists.txt
@@ -307,9 +307,11 @@
 
 include(HandleLibCXXABI) # Setup the ABI library flags
 
-# Remove flags that may have snuck in.
-remove_flags(-DNDEBUG -UNDEBUG -D_DEBUG
-             -stdlib=libc++ -stdlib=libstdc++ -lc++abi -m32)
+if (LIBCXX_STANDALONE_BUILD)
+  # Remove flags that may have snuck in.
+  remove_flags(-DNDEBUG -UNDEBUG -D_DEBUG
+               -stdlib=libc++ -stdlib=libstdc++ -lc++abi -m32)
+endif()
 
 # FIXME(EricWF): See the FIXME on LIBCXX_ENABLE_PEDANTIC.
 # Remove the -pedantic flag and -Wno-pedantic and -pedantic-errors