if !cast<A>("").x then
  def x;

[189/189] Building CXX object unittests/ADT/CMakeFiles/ADTTests.dir/STLExtrasTest.cpp.o
FAILED: unittests/ADT/CMakeFiles/ADTTests.dir/STLExtrasTest.cpp.o 
/usr/lib/ccache/clang++ -DEXPENSIVE_CHECKS -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GLIBCXX_DEBUG -D_GNU_SOURCE -D_LIBCPP_ENABLE_ASSERTIONS -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/jayfoad2/llvm-expensive/unittests/ADT -I/home/jayfoad2/git/llvm-project/llvm/unittests/ADT -I/home/jayfoad2/llvm-expensive/include -I/home/jayfoad2/git/llvm-project/llvm/include -I/home/jayfoad2/git/llvm-project/third-party/unittest/googletest/include -I/home/jayfoad2/git/llvm-project/third-party/unittest/googlemock/include -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -g  -Wno-variadic-macros -Wno-gnu-zero-variadic-macro-arguments -fno-exceptions -fno-rtti -Wno-suggest-override -std=c++17 -MD -MT unittests/ADT/CMakeFiles/ADTTests.dir/STLExtrasTest.cpp.o -MF unittests/ADT/CMakeFiles/ADTTests.dir/STLExtrasTest.cpp.o.d -o unittests/ADT/CMakeFiles/ADTTests.dir/STLExtrasTest.cpp.o -c /home/jayfoad2/git/llvm-project/llvm/unittests/ADT/STLExtrasTest.cpp
In file included from /home/jayfoad2/git/llvm-project/llvm/unittests/ADT/STLExtrasTest.cpp:9:
In file included from /home/jayfoad2/git/llvm-project/llvm/include/llvm/ADT/STLExtras.h:20:
In file included from /home/jayfoad2/git/llvm-project/llvm/include/llvm/ADT/Hashing.h:51:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/12/../../../../include/c++/12/algorithm:60:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/12/../../../../include/c++/12/bits/stl_algobase.h:69:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/12/../../../../include/c++/12/debug/debug.h:133:
/usr/bin/../lib/gcc/x86_64-linux-gnu/12/../../../../include/c++/12/debug/functions.h:110:44: error: no matching function for call to '__addressof'
      return __foreign_iterator_aux4(__it, std::__addressof(*__other));
                                           ^~~~~~~~~~~~~~~~
/usr/bin/../lib/gcc/x86_64-linux-gnu/12/../../../../include/c++/12/debug/functions.h:164:14: note: in instantiation of function template specialization '__gnu_debug::__foreign_iterator_aux3<__gnu_cxx::__normal_iterator<const int *, std::__cxx1998::vector<int>>, std::vector<int>, std::random_access_iterator_tag, llvm::detail::SafeIntIterator<int, false>>' requested here
      return __foreign_iterator_aux3(__it, __other, __other_end, __tag());
             ^
/usr/bin/../lib/gcc/x86_64-linux-gnu/12/../../../../include/c++/12/debug/functions.h:186:5: note: in instantiation of function template specialization '__gnu_debug::__foreign_iterator_aux2<__gnu_cxx::__normal_iterator<const int *, std::__cxx1998::vector<int>>, std::vector<int>, std::random_access_iterator_tag, llvm::detail::SafeIntIterator<int, false>>' requested here
        || __foreign_iterator_aux2(__it, std::__miter_base(__other),
           ^
/usr/bin/../lib/gcc/x86_64-linux-gnu/12/../../../../include/c++/12/debug/functions.h:198:14: note: in instantiation of function template specialization '__gnu_debug::__foreign_iterator_aux<__gnu_cxx::__normal_iterator<const int *, std::__cxx1998::vector<int>>, std::vector<int>, std::random_access_iterator_tag, llvm::detail::SafeIntIterator<int, false>>' requested here
      return __foreign_iterator_aux(__it, __other, __other_end, _Integral());
             ^
/usr/bin/../lib/gcc/x86_64-linux-gnu/12/../../../../include/c++/12/debug/vector:626:4: note: in instantiation of function template specialization '__gnu_debug::__foreign_iterator<__gnu_cxx::__normal_iterator<const int *, std::__cxx1998::vector<int>>, std::vector<int>, std::random_access_iterator_tag, llvm::detail::SafeIntIterator<int, false>>' requested here
          __glibcxx_check_insert_range(__position, __first, __last, __dist);
          ^
/usr/bin/../lib/gcc/x86_64-linux-gnu/12/../../../../include/c++/12/debug/macros.h:183:36: note: expanded from macro '__glibcxx_check_insert_range'
_GLIBCXX_DEBUG_VERIFY(__gnu_debug::__foreign_iterator(_Position,_First,_Last),\
                                   ^
/home/jayfoad2/git/llvm-project/llvm/include/llvm/ADT/STLExtras.h:2017:5: note: in instantiation of function template specialization 'std::vector<int>::insert<llvm::detail::SafeIntIterator<int, false>, void>' requested here
  C.insert(C.end(), adl_begin(R), adl_end(R));
    ^
/home/jayfoad2/git/llvm-project/llvm/unittests/ADT/STLExtrasTest.cpp:367:3: note: in instantiation of function template specialization 'llvm::append_range<std::vector<int>, llvm::iota_range<int>>' requested here
  append_range(V, llvm::seq(6, 8));
  ^
/usr/bin/../lib/gcc/x86_64-linux-gnu/12/../../../../include/c++/12/bits/move.h:49:5: note: candidate function [with _Tp = int] not viable: expects an lvalue for 1st argument
    __addressof(_Tp& __r) _GLIBCXX_NOEXCEPT
    ^
1 error generated.
ninja: build stopped: subcommand failed.