diff --git a/include/Config/config.h.in b/include/Config/config.h.in
index d7c0bbf18d5..2cae4b35549 100644
--- a/include/Config/config.h.in
+++ b/include/Config/config.h.in
@@ -15,6 +15,9 @@
    */
 #undef HAVE_ALLOCA_H
 
+/* Define to 1 if you have the `backtrace' function. */
+#undef HAVE_BACKTRACE
+
 /* define if the compiler has bidirectional iterator */
 #undef HAVE_BI_ITERATOR
 
@@ -24,6 +27,9 @@
 /* Define if dlopen() is available on this platform. */
 #undef HAVE_DLOPEN
 
+/* Define to 1 if you have the <execinfo.h> header file. */
+#undef HAVE_EXECINFO_H
+
 /* define if the compiler has ext/slist */
 #undef HAVE_EXT_SLIST
 
diff --git a/include/llvm/Config/config.h.in b/include/llvm/Config/config.h.in
index d7c0bbf18d5..2cae4b35549 100644
--- a/include/llvm/Config/config.h.in
+++ b/include/llvm/Config/config.h.in
@@ -15,6 +15,9 @@
    */
 #undef HAVE_ALLOCA_H
 
+/* Define to 1 if you have the `backtrace' function. */
+#undef HAVE_BACKTRACE
+
 /* define if the compiler has bidirectional iterator */
 #undef HAVE_BI_ITERATOR
 
@@ -24,6 +27,9 @@
 /* Define if dlopen() is available on this platform. */
 #undef HAVE_DLOPEN
 
+/* Define to 1 if you have the <execinfo.h> header file. */
+#undef HAVE_EXECINFO_H
+
 /* define if the compiler has ext/slist */
 #undef HAVE_EXT_SLIST