diff --git a/include/llvm/Config/config.h.cmake b/include/llvm/Config/config.h.cmake
index 37696eb473b..d107c8f030b 100644
--- a/include/llvm/Config/config.h.cmake
+++ b/include/llvm/Config/config.h.cmake
@@ -518,9 +518,6 @@
 /* Type of 1st arg on ELM Callback */
 #cmakedefine WIN32_ELMCB_PCSTR ${WIN32_ELMCB_PCSTR}
 
-/* Define to empty if `const' does not conform to ANSI C. */
-#undef const
-
 /* Define to `int' if <sys/types.h> does not define. */
 #undef pid_t