diff --git a/libcxx/include/__config b/libcxx/include/__config
--- a/libcxx/include/__config
+++ b/libcxx/include/__config
@@ -127,6 +127,11 @@
 // reduces the number of weak definitions generated in programs that use
 // iostreams by providing a single strong definition in the shared library.
 # define _LIBCPP_ABI_ENABLE_ADDITIONAL_IOSTREAM_EXPLICIT_INSTANTIATIONS_1
+
+// Define a key function for `bad_function_call` in the library, to centralize
+// its vtable and typeinfo to libc++ rather than having all other libraries
+// using that class define their own copies.
+#  define _LIBCPP_ABI_BAD_FUNCTION_CALL_KEY_FUNCTION
 #endif
 
 #define _LIBCPP_CONCAT1(_LIBCPP_X,_LIBCPP_Y) _LIBCPP_X##_LIBCPP_Y
diff --git a/libcxx/lib/abi/CHANGELOG.TXT b/libcxx/lib/abi/CHANGELOG.TXT
--- a/libcxx/lib/abi/CHANGELOG.TXT
+++ b/libcxx/lib/abi/CHANGELOG.TXT
@@ -12,6 +12,39 @@
 
 New entries should be added directly below the "Version" header.
 
+------------
+Version 14.0
+------------
+
+* [libc++] Always define a key function for std::bad_function_call in the dylib
+
+  This commit added a new explicit instantiation of std::bad_function_call's
+  vtable in the shared library. This change is not an ABI break as it only
+  adds symbols to the library. Programs compiled against the library will not
+  rely on the vtable being defined in it by default. Reliance on the vtable
+  being in the shared library can be enabled by defining the
+  _LIBCPP_ABI_BAD_FUNCTION_CALL_KEY_FUNCTION macro.
+
+  x86_64-apple-apple-darwin
+  -------------------------
+  Symbol added: __ZNKSt3__117bad_function_call4whatEv
+  Symbol added: __ZNSt3__117bad_function_callD0Ev
+  Symbol added: __ZNSt3__117bad_function_callD1Ev
+  Symbol added: __ZNSt3__117bad_function_callD2Ev
+  Symbol added: __ZTINSt3__117bad_function_callE
+  Symbol added: __ZTSNSt3__117bad_function_callE
+  Symbol added: __ZTVNSt3__117bad_function_callE
+
+  x86_64-unknown-linux-gnu
+  ------------------------
+  Symbol added: _ZNKSt3__117bad_function_call4whatEv
+  Symbol added: _ZNSt3__117bad_function_callD0Ev
+  Symbol added: _ZNSt3__117bad_function_callD1Ev
+  Symbol added: _ZNSt3__117bad_function_callD2Ev
+  Symbol added: _ZTINSt3__117bad_function_callE
+  Symbol added: _ZTSNSt3__117bad_function_callE
+  Symbol added: _ZTVNSt3__117bad_function_callE
+
 ------------
 Version 12.0
 ------------
diff --git a/libcxx/lib/abi/x86_64-apple-darwin.libcxxabi.v1.stable.exceptions.no_new_in_libcxx.abilist b/libcxx/lib/abi/x86_64-apple-darwin.libcxxabi.v1.stable.exceptions.no_new_in_libcxx.abilist
--- a/libcxx/lib/abi/x86_64-apple-darwin.libcxxabi.v1.stable.exceptions.no_new_in_libcxx.abilist
+++ b/libcxx/lib/abi/x86_64-apple-darwin.libcxxabi.v1.stable.exceptions.no_new_in_libcxx.abilist
@@ -497,6 +497,7 @@
 {'is_defined': True, 'name': '__ZNKSt3__115basic_streambufIwNS_11char_traitsIwEEE6getlocEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '__ZNKSt3__115basic_stringbufIcNS_11char_traitsIcEENS_9allocatorIcEEE3strEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '__ZNKSt3__115error_condition7messageEv', 'type': 'FUNC'}
+{'is_defined': True, 'name': '__ZNKSt3__117bad_function_call4whatEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '__ZNKSt3__117moneypunct_bynameIcLb0EE11do_groupingEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '__ZNKSt3__117moneypunct_bynameIcLb0EE13do_neg_formatEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '__ZNKSt3__117moneypunct_bynameIcLb0EE13do_pos_formatEv', 'type': 'FUNC'}
@@ -1482,6 +1483,9 @@
 {'is_defined': True, 'name': '__ZNSt3__117__widen_from_utf8ILm32EED0Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '__ZNSt3__117__widen_from_utf8ILm32EED1Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '__ZNSt3__117__widen_from_utf8ILm32EED2Ev', 'type': 'FUNC'}
+{'is_defined': True, 'name': '__ZNSt3__117bad_function_callD0Ev', 'type': 'FUNC'}
+{'is_defined': True, 'name': '__ZNSt3__117bad_function_callD1Ev', 'type': 'FUNC'}
+{'is_defined': True, 'name': '__ZNSt3__117bad_function_callD2Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '__ZNSt3__117declare_reachableEPv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '__ZNSt3__117iostream_categoryEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '__ZNSt3__117moneypunct_bynameIcLb0EE4initEPKc', 'type': 'FUNC'}
@@ -2037,6 +2041,7 @@
 {'is_defined': True, 'name': '__ZTINSt3__117__assoc_sub_stateE', 'size': 0, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '__ZTINSt3__117__widen_from_utf8ILm16EEE', 'size': 0, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '__ZTINSt3__117__widen_from_utf8ILm32EEE', 'size': 0, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '__ZTINSt3__117bad_function_callE', 'size': 0, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '__ZTINSt3__117moneypunct_bynameIcLb0EEE', 'size': 0, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '__ZTINSt3__117moneypunct_bynameIcLb1EEE', 'size': 0, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '__ZTINSt3__117moneypunct_bynameIwLb0EEE', 'size': 0, 'type': 'OBJECT'}
@@ -2223,6 +2228,7 @@
 {'is_defined': True, 'name': '__ZTSNSt3__115time_get_bynameIwNS_19istreambuf_iteratorIwNS_11char_traitsIwEEEEEE', 'size': 0, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '__ZTSNSt3__115time_put_bynameIcNS_19ostreambuf_iteratorIcNS_11char_traitsIcEEEEEE', 'size': 0, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '__ZTSNSt3__115time_put_bynameIwNS_19ostreambuf_iteratorIwNS_11char_traitsIwEEEEEE', 'size': 0, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '__ZTSNSt3__117bad_function_callE', 'size': 0, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '__ZTSNSt3__117moneypunct_bynameIcLb0EEE', 'size': 0, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '__ZTSNSt3__117moneypunct_bynameIcLb1EEE', 'size': 0, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '__ZTSNSt3__117moneypunct_bynameIwLb0EEE', 'size': 0, 'type': 'OBJECT'}
@@ -2428,6 +2434,7 @@
 {'is_defined': True, 'name': '__ZTVNSt3__117__assoc_sub_stateE', 'size': 0, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '__ZTVNSt3__117__widen_from_utf8ILm16EEE', 'size': 0, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '__ZTVNSt3__117__widen_from_utf8ILm32EEE', 'size': 0, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '__ZTVNSt3__117bad_function_callE', 'size': 0, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '__ZTVNSt3__117moneypunct_bynameIcLb0EEE', 'size': 0, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '__ZTVNSt3__117moneypunct_bynameIcLb1EEE', 'size': 0, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '__ZTVNSt3__117moneypunct_bynameIwLb0EEE', 'size': 0, 'type': 'OBJECT'}
diff --git a/libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.exceptions.no_new_in_libcxx.abilist b/libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.exceptions.no_new_in_libcxx.abilist
--- a/libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.exceptions.no_new_in_libcxx.abilist
+++ b/libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.exceptions.no_new_in_libcxx.abilist
@@ -230,6 +230,7 @@
 {'is_defined': True, 'name': '_ZNKSt3__115basic_streambufIwNS_11char_traitsIwEEE6getlocEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNKSt3__115basic_stringbufIcNS_11char_traitsIcEENS_9allocatorIcEEE3strEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNKSt3__115error_condition7messageEv', 'type': 'FUNC'}
+{'is_defined': True, 'name': '_ZNKSt3__117bad_function_call4whatEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNKSt3__117moneypunct_bynameIcLb0EE11do_groupingEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNKSt3__117moneypunct_bynameIcLb0EE13do_neg_formatEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNKSt3__117moneypunct_bynameIcLb0EE13do_pos_formatEv', 'type': 'FUNC'}
@@ -1172,6 +1173,9 @@
 {'is_defined': True, 'name': '_ZNSt3__117__widen_from_utf8ILm32EED0Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__117__widen_from_utf8ILm32EED1Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__117__widen_from_utf8ILm32EED2Ev', 'type': 'FUNC'}
+{'is_defined': True, 'name': '_ZNSt3__117bad_function_callD0Ev', 'type': 'FUNC'}
+{'is_defined': True, 'name': '_ZNSt3__117bad_function_callD1Ev', 'type': 'FUNC'}
+{'is_defined': True, 'name': '_ZNSt3__117bad_function_callD2Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__117declare_reachableEPv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__117iostream_categoryEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__117moneypunct_bynameIcLb0EE4initEPKc', 'type': 'FUNC'}
@@ -1703,6 +1707,7 @@
 {'is_defined': True, 'name': '_ZTINSt3__117__assoc_sub_stateE', 'size': 24, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZTINSt3__117__widen_from_utf8ILm16EEE', 'size': 24, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZTINSt3__117__widen_from_utf8ILm32EEE', 'size': 24, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZTINSt3__117bad_function_callE', 'size': 24, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZTINSt3__117moneypunct_bynameIcLb0EEE', 'size': 24, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZTINSt3__117moneypunct_bynameIcLb1EEE', 'size': 24, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZTINSt3__117moneypunct_bynameIwLb0EEE', 'size': 24, 'type': 'OBJECT'}
@@ -1832,6 +1837,7 @@
 {'is_defined': True, 'name': '_ZTSNSt3__117__assoc_sub_stateE', 'size': 28, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZTSNSt3__117__widen_from_utf8ILm16EEE', 'size': 35, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZTSNSt3__117__widen_from_utf8ILm32EEE', 'size': 35, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZTSNSt3__117bad_function_callE', 'size': 28, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZTSNSt3__117moneypunct_bynameIcLb0EEE', 'size': 35, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZTSNSt3__117moneypunct_bynameIcLb1EEE', 'size': 35, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZTSNSt3__117moneypunct_bynameIwLb0EEE', 'size': 35, 'type': 'OBJECT'}
@@ -1962,6 +1968,7 @@
 {'is_defined': True, 'name': '_ZTVNSt3__117__assoc_sub_stateE', 'size': 48, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZTVNSt3__117__widen_from_utf8ILm16EEE', 'size': 96, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZTVNSt3__117__widen_from_utf8ILm32EEE', 'size': 96, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZTVNSt3__117bad_function_callE', 'size': 40, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZTVNSt3__117moneypunct_bynameIcLb0EEE', 'size': 112, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZTVNSt3__117moneypunct_bynameIcLb1EEE', 'size': 112, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZTVNSt3__117moneypunct_bynameIwLb0EEE', 'size': 112, 'type': 'OBJECT'}