[llvm] Be explicit about what libstdc++ C++11 ABI to use (PR #154447)

Fri Aug 22 01:08:47 PDT 2025

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-aarch64-sve2-vla` running on `linaro-g4-02` while building `llvm` at step 7 "ninja check 1".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/198/builds/7141

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 7 (ninja check 1) failure: stage 1 checked (failure)
...
[155/171] Building CXX object flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Pointer.cpp.o
[156/171] Building CXX object flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/RuntimeCrashTest.cpp.o
[157/171] Building CXX object flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Matmul.cpp.o
[158/171] Building CXX object flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Namelist.cpp.o
[159/171] Building CXX object flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/MatmulTranspose.cpp.o
[160/171] Building CXX object flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/CharacterTest.cpp.o
[161/171] Building CXX object flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/NumericalFormatTest.cpp.o
[162/171] Building CXX object flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Transformational.cpp.o
[163/171] Building CXX object flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Reduction.cpp.o
[164/171] Linking CXX executable flang-rt/unittests/Runtime/RuntimeTests
FAILED: flang-rt/unittests/Runtime/RuntimeTests 
: && /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/stage1/./bin/clang++ --target=aarch64-unknown-linux-gnu -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 -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 -ffunction-sections -fdata-sections -O3 -DNDEBUG -fuse-ld=lld -Wl,--color-diagnostics    -Wl,--gc-sections flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/AccessTest.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Allocatable.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/ArrayConstructor.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Assign.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/BufferTest.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/CharacterTest.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/CommandTest.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Complex.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/CrashHandlerFixture.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Derived.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Descriptor.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/ExternalIOTest.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Format.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/InputExtensions.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Inquiry.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/ListInputTest.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/LogicalFormatTest.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Matmul.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/MatmulTranspose.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/MiscIntrinsic.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Namelist.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Numeric.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/NumericalFormatTest.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Pointer.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Ragged.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Random.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Reduction.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/RuntimeCrashTest.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Stop.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Support.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Time.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/TemporaryStack.cpp.o flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Transformational.cpp.o -o flang-rt/unittests/Runtime/RuntimeTests  /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/stage1/lib/libLLVMSupport.a  /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/stage1/lib/libllvm_gtest_main.a  /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/stage1/lib/libllvm_gtest.a  /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/stage1/lib/clang/22/lib/aarch64-unknown-linux-gnu/libflang_rt.runtime.a  /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/stage1/lib/libLLVMSupport.a  -lrt  -ldl  -lm  /usr/lib/aarch64-linux-gnu/libz.so  /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/stage1/lib/libLLVMDemangle.a  -lpthread && :
ld.lld: error: undefined symbol: testing::internal::GetBoolAssertionFailureMessage[abi:cxx11](testing::AssertionResult const&, char const*, char const*, char const*)
>>> referenced by AccessTest.cpp
>>>               flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/AccessTest.cpp.o:(AccessTests_TestExists_Test::TestBody())
>>> referenced by ArrayConstructor.cpp
>>>               flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/ArrayConstructor.cpp.o:(ArrayConstructor_Basic_Test::TestBody())
>>> referenced by Assign.cpp
>>>               flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Assign.cpp.o:(Assign__FortranACopyInAssign_Test::TestBody())
>>> referenced 338 more times

ld.lld: error: undefined symbol: testing::internal::EqFailure(char const*, char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>> const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>> const&, bool)
>>> referenced by Assign.cpp
>>>               flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Assign.cpp.o:(testing::AssertionResult testing::internal::CmpHelperEQ<Fortran::runtime::TypeCode, Fortran::runtime::TypeCode>(char const*, char const*, Fortran::runtime::TypeCode const&, Fortran::runtime::TypeCode const&))
>>> referenced by BufferTest.cpp
>>>               flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/BufferTest.cpp.o:(BufferTests_TestFrameBufferReadAndWrite_Test::TestBody())
>>> referenced by Allocatable.cpp
>>>               flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Allocatable.cpp.o:(testing::AssertionResult testing::internal::CmpHelperEQ<std::basic_string_view<char, std::char_traits<char>>, char [50]>(char const*, char const*, std::basic_string_view<char, std::char_traits<char>> const&, char const (&) [50]))
>>> referenced 46 more times

ld.lld: error: undefined symbol: testing::internal::PrintStringTo(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>> const&, std::ostream*)
>>> referenced by Allocatable.cpp
>>>               flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Allocatable.cpp.o:(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>> testing::PrintToString<std::basic_string_view<char, std::char_traits<char>>>(std::basic_string_view<char, std::char_traits<char>> const&))
>>> referenced by CharacterTest.cpp
>>>               flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/CharacterTest.cpp.o:(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>> testing::PrintToString<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>>(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>> const&))
>>> referenced by ArrayConstructor.cpp
>>>               flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/ArrayConstructor.cpp.o:(testing::internal::MatchesRegexMatcher::DescribeTo(std::ostream*) const)
>>> referenced 4 more times

ld.lld: error: undefined symbol: testing::internal::DeathTest::Create(char const*, testing::Matcher<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>> const&>, char const*, int, testing::internal::DeathTest**)
>>> referenced by CommandTest.cpp
>>>               flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/CommandTest.cpp.o:(ZeroArguments_ECLInvalidCommandTerminatedSync_Test::TestBody())
>>> referenced by ArrayConstructor.cpp
>>>               flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/ArrayConstructor.cpp.o:(ArrayConstructor_CharacterRuntimeCheck_Test::TestBody())
>>> referenced by Format.cpp
>>>               flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Format.cpp.o:(InvalidFormatFailure_ParenMismatch_Test::TestBody())
>>> referenced 33 more times

ld.lld: error: undefined symbol: testing::internal::PrintU16StringTo(std::__cxx11::basic_string<char16_t, std::char_traits<char16_t>, std::allocator<char16_t>> const&, std::ostream*)

```

</details>

https://github.com/llvm/llvm-project/pull/154447