diff --git a/libcxx/include/__config b/libcxx/include/__config
--- a/libcxx/include/__config
+++ b/libcxx/include/__config
@@ -82,6 +82,9 @@
 // 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
+// Override the default return value of `what()` function that comes from
+// `std::exception` with a string that is specific to `bad_function_call`.
+#  define _LIBCPP_ABI_BAD_FUNCTION_CALL_GOOD_WHAT_MESSAGE
 // Enable optimized version of __do_get_(un)signed which avoids redundant copies.
 #  define _LIBCPP_ABI_OPTIMIZED_LOCALE_NUM_GET
 // In C++20 and later, don't derive std::plus from std::binary_function,
diff --git a/libcxx/include/__functional/function.h b/libcxx/include/__functional/function.h
--- a/libcxx/include/__functional/function.h
+++ b/libcxx/include/__functional/function.h
@@ -35,10 +35,21 @@
 class _LIBCPP_EXCEPTION_ABI bad_function_call
     : public exception
 {
-#ifdef _LIBCPP_ABI_BAD_FUNCTION_CALL_KEY_FUNCTION
 public:
+// Using a key function allows emitting a vtable and typeinfo for the class in
+// a single translation unit. Originally `bad_function_call` didn't use a key
+// function, and because changing this behavior constitutes an ABI break,
+// it is controlled by a preprocessor definition.
+#ifdef _LIBCPP_ABI_BAD_FUNCTION_CALL_KEY_FUNCTION
     virtual ~bad_function_call() _NOEXCEPT;
+#else
+    virtual ~bad_function_call() _NOEXCEPT {}
+#endif
 
+// Whether to use a `what` message specific to `bad_function_call`. This
+// behavior is controlled by a preprocessor definition because changing it
+// constitutes an ABI break (with `what` serving as a key function).
+#ifdef _LIBCPP_ABI_BAD_FUNCTION_CALL_GOOD_WHAT_MESSAGE
     virtual const char* what() const _NOEXCEPT;
 #endif
 };
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
@@ -27,7 +27,6 @@
 
   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
@@ -37,7 +36,6 @@
 
   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
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
@@ -497,7 +497,6 @@
 {'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'}
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
@@ -1,5 +1,6 @@
 {'is_defined': False, 'name': '_ZNKSt11logic_error4whatEv', 'type': 'FUNC'}
 {'is_defined': False, 'name': '_ZNKSt13runtime_error4whatEv', 'type': 'FUNC'}
+{'is_defined': False, 'name': '_ZNKSt9exception4whatEv', 'type': 'FUNC'}
 {'is_defined': False, 'name': '_ZNSt11logic_errorD2Ev', 'type': 'FUNC'}
 {'is_defined': False, 'name': '_ZNSt12length_errorD1Ev', 'type': 'FUNC'}
 {'is_defined': False, 'name': '_ZNSt12out_of_rangeD1Ev', 'type': 'FUNC'}
@@ -35,12 +36,15 @@
 {'is_defined': False, 'name': '_ZTVSt13runtime_error', 'size': 0, 'type': 'OBJECT'}
 {'is_defined': False, 'name': '_ZTVSt14overflow_error', 'size': 0, 'type': 'OBJECT'}
 {'is_defined': False, 'name': '_ZTVSt16invalid_argument', 'size': 0, 'type': 'OBJECT'}
+{'is_defined': False, 'name': '_ZTVSt9exception', 'size': 0, 'type': 'OBJECT'}
 {'is_defined': False, 'name': '_ZdaPv', 'type': 'FUNC'}
 {'is_defined': False, 'name': '_ZdaPvSt11align_val_t', 'type': 'FUNC'}
 {'is_defined': False, 'name': '_ZdlPv', 'type': 'FUNC'}
+{'is_defined': False, 'name': '_ZdlPvSt11align_val_t', 'type': 'FUNC'}
 {'is_defined': False, 'name': '_Znam', 'type': 'FUNC'}
 {'is_defined': False, 'name': '_ZnamSt11align_val_t', 'type': 'FUNC'}
 {'is_defined': False, 'name': '_Znwm', 'type': 'FUNC'}
+{'is_defined': False, 'name': '_ZnwmSt11align_val_t', 'type': 'FUNC'}
 {'is_defined': False, 'name': '__cxa_allocate_exception', 'type': 'FUNC'}
 {'is_defined': False, 'name': '__cxa_begin_catch', 'type': 'FUNC'}
 {'is_defined': False, 'name': '__cxa_current_primary_exception', 'type': 'FUNC'}
@@ -230,7 +234,6 @@
 {'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'}
@@ -1980,6 +1983,8 @@
 {'is_defined': True, 'name': '_ZTVNSt3__120__codecvt_utf8_utf16IDiEE', 'size': 96, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZTVNSt3__120__codecvt_utf8_utf16IDsEE', 'size': 96, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZTVNSt3__120__codecvt_utf8_utf16IwEE', 'size': 96, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZTVNSt3__120__time_get_c_storageIcEE', 'size': 72, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZTVNSt3__120__time_get_c_storageIwEE', 'size': 72, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZTVNSt3__14__fs10filesystem16filesystem_errorE', 'size': 40, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZTVNSt3__15ctypeIcEE', 'size': 104, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZTVNSt3__15ctypeIwEE', 'size': 136, 'type': 'OBJECT'}
diff --git a/libcxx/src/functional.cpp b/libcxx/src/functional.cpp
--- a/libcxx/src/functional.cpp
+++ b/libcxx/src/functional.cpp
@@ -14,7 +14,9 @@
 bad_function_call::~bad_function_call() noexcept
 {
 }
+#endif
 
+#ifdef _LIBCPP_ABI_BAD_FUNCTION_CALL_GOOD_WHAT_MESSAGE
 const char*
 bad_function_call::what() const noexcept
 {
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.inv/invoke.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.inv/invoke.pass.cpp
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.inv/invoke.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.inv/invoke.pass.cpp
@@ -15,6 +15,19 @@
 // This test runs in C++03, but we have deprecated using std::function in C++03.
 // ADDITIONAL_COMPILE_FLAGS: -D_LIBCPP_DISABLE_DEPRECATION_WARNINGS
 
+// Address Sanitizer doesn't instrument weak symbols on Linux. Because the key
+// function is conditionally defined for bad_function_call, its typeinfo and
+// vtable will be defined as strong symbols in the library and weak symbols in
+// other translation units. Only the strong symbol will be instrumented,
+// increasing its size and leading to a serious ODR violation resulting in
+// a crash.
+// Some relevant bugs:
+// https://github.com/google/sanitizers/issues/1017
+// https://github.com/google/sanitizers/issues/619
+// https://github.com/google/sanitizers/issues/398
+// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68016
+// UNSUPPORTED: asan
+
 #include <functional>
 #include <cassert>