Index: CMakeLists.txt
===================================================================
--- CMakeLists.txt
+++ CMakeLists.txt
@@ -396,9 +396,6 @@
 set(LLVM_ABI_BREAKING_CHECKS "WITH_ASSERTS" CACHE STRING
   "Enable abi-breaking checks.  Can be WITH_ASSERTS, FORCE_ON or FORCE_OFF.")
 
-option(LLVM_DISABLE_ABI_BREAKING_CHECKS_ENFORCING
-  "Disable abi-breaking checks mismatch detection at link-tim." OFF)
-
 option(LLVM_FORCE_USE_OLD_HOST_TOOLCHAIN
        "Set to ON to force using an old, unsupported host toolchain." OFF)
 
Index: llvm/Config/abi-breaking.h.cmake
===================================================================
--- llvm/Config/abi-breaking.h.cmake
+++ llvm/Config/abi-breaking.h.cmake
@@ -15,11 +15,8 @@
 /* Define to enable checks that alter the LLVM C++ ABI */
 #cmakedefine01 LLVM_ENABLE_ABI_BREAKING_CHECKS
 
-/* Define to disable the link-time checking of mismatch for
-   LLVM_ENABLE_ABI_BREAKING_CHECKS */
-#ifndef LLVM_DISABLE_ABI_BREAKING_CHECKS_ENFORCING
-#cmakedefine01 LLVM_DISABLE_ABI_BREAKING_CHECKS_ENFORCING
-#endif
+/* Allow selectively disabling link-time mismatch checking so that header-only
+   ADT content from LLVM can be used without linking libSupport. */
 #if !LLVM_DISABLE_ABI_BREAKING_CHECKS_ENFORCING
 
 // ABI_BREAKING_CHECKS protection: provides link-time failure when clients build