[llvm] [flang-rt] Optimise ShallowCopy and use it in CopyInAssign (PR #140569)

Thu May 22 07:55:17 PDT 2025

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `openmp-offload-sles-build-only` running on `rocm-worker-hw-04-sles` while building `flang-rt` at step 5 "compile-openmp".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/140/builds/23618

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

```
Step 5 (compile-openmp) failure: build (failure)
...
7.859 [77/34/865] Linking CXX shared library /home/botworker/bbot/builds/openmp-offload-sles-build/llvm.build/lib/clang/21/lib/x86_64-unknown-linux-gnu/libclang_rt.tsan.so
8.009 [76/34/866] Building CXX object offload/tools/offload-tblgen/CMakeFiles/offload-tblgen.dir/offload-tblgen.cpp.o
8.016 [75/34/867] Building CXX object offload/tools/kernelreplay/CMakeFiles/llvm-omp-kernel-replay.dir/llvm-omp-kernel-replay.cpp.o
8.034 [74/34/868] Building CXX object offload/tools/offload-tblgen/CMakeFiles/offload-tblgen.dir/MiscGen.cpp.o
8.090 [73/34/869] Building CXX object flang-rt/lib/runtime/CMakeFiles/flang_rt.runtime.static.dir/allocatable.cpp.o
8.266 [72/34/870] Building CXX object flang-rt/lib/runtime/CMakeFiles/flang_rt.runtime.static.dir/home/botworker/bbot/builds/openmp-offload-sles-build/llvm.src/flang/lib/Decimal/decimal-to-binary.cpp.o
8.296 [71/34/871] Building CXX object flang-rt/lib/runtime/CMakeFiles/flang_rt.runtime.static.dir/buffer.cpp.o
8.333 [70/34/872] Building CXX object flang-rt/lib/runtime/CMakeFiles/flang_rt.runtime.static.dir/array-constructor.cpp.o
8.426 [69/34/873] Building CXX object offload/tools/offload-tblgen/CMakeFiles/offload-tblgen.dir/EntryPointGen.cpp.o
8.454 [68/34/874] Building CXX object flang-rt/lib/runtime/CMakeFiles/flang_rt.runtime.static.dir/assign.cpp.o
FAILED: flang-rt/lib/runtime/CMakeFiles/flang_rt.runtime.static.dir/assign.cpp.o 
/home/botworker/bbot/builds/openmp-offload-sles-build/llvm.build/./bin/clang++ --target=x86_64-unknown-linux-gnu -D_DEBUG -D_GLIBCXX_ASSERTIONS -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/botworker/bbot/builds/openmp-offload-sles-build/llvm.src/flang-rt/include -I/home/botworker/bbot/builds/openmp-offload-sles-build/llvm.src/flang-rt/../flang/include -Iflang-rt -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 -Wno-unnecessary-virtual-specifier -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -O3 -DNDEBUG -UNDEBUG -fno-lto -fno-exceptions -fno-rtti -funwind-tables -fno-asynchronous-unwind-tables -U_GLIBCXX_ASSERTIONS -U_LIBCPP_ENABLE_ASSERTIONS -std=gnu++17 -MD -MT flang-rt/lib/runtime/CMakeFiles/flang_rt.runtime.static.dir/assign.cpp.o -MF flang-rt/lib/runtime/CMakeFiles/flang_rt.runtime.static.dir/assign.cpp.o.d -o flang-rt/lib/runtime/CMakeFiles/flang_rt.runtime.static.dir/assign.cpp.o -c /home/botworker/bbot/builds/openmp-offload-sles-build/llvm.src/flang-rt/lib/runtime/assign.cpp
/home/botworker/bbot/builds/openmp-offload-sles-build/llvm.src/flang-rt/lib/runtime/assign.cpp:594:17: error: use of undeclared identifier 'kNoAsyncId'
  594 |   temp.Allocate(kNoAsyncId);
      |                 ^~~~~~~~~~
1 error generated.
8.472 [68/33/875] Building CXX object offload/tools/offload-tblgen/CMakeFiles/offload-tblgen.dir/PrintGen.cpp.o
8.485 [68/32/876] Building CXX object flang-rt/lib/runtime/CMakeFiles/flang_rt.runtime.static.dir/home/botworker/bbot/builds/openmp-offload-sles-build/llvm.src/flang/lib/Decimal/binary-to-decimal.cpp.o
8.597 [68/31/877] Building CXX object flang-rt/lib/runtime/CMakeFiles/flang_rt.runtime.static.dir/connection.cpp.o
8.672 [68/30/878] Building CXX object flang-rt/lib/runtime/CMakeFiles/flang_rt.runtime.static.dir/copy.cpp.o
8.688 [68/29/879] Building CXX object flang-rt/lib/runtime/CMakeFiles/flang_rt.runtime.static.dir/derived-api.cpp.o
8.765 [68/28/880] Building CXX object offload/tools/offload-tblgen/CMakeFiles/offload-tblgen.dir/APIGen.cpp.o
8.777 [68/27/881] Building CXX object flang-rt/lib/runtime/CMakeFiles/flang_rt.runtime.static.dir/descriptor.cpp.o
8.936 [68/26/882] Building CXX object flang-rt/lib/runtime/CMakeFiles/flang_rt.runtime.static.dir/derived.cpp.o
9.079 [68/25/883] Building CXX object flang-rt/lib/runtime/CMakeFiles/flang_rt.runtime.static.dir/descriptor-io.cpp.o
9.234 [68/24/884] Building CXX object offload/plugins-nextgen/host/CMakeFiles/omptarget.rtl.host.dir/src/rtl.cpp.o
9.363 [68/23/885] Building CXX object offload/libomptarget/CMakeFiles/omptarget.dir/LegacyAPI.cpp.o
9.385 [68/22/886] Building CXX object offload/plugins-nextgen/common/CMakeFiles/PluginCommon.dir/src/GlobalHandler.cpp.o
9.416 [68/21/887] Building CXX object offload/plugins-nextgen/common/CMakeFiles/PluginCommon.dir/src/PluginInterface.cpp.o
9.547 [68/20/888] Building CXX object flang-rt/lib/runtime/CMakeFiles/flang_rt.runtime.static.dir/edit-input.cpp.o
9.567 [68/19/889] Building CXX object offload/libomptarget/CMakeFiles/omptarget.dir/OffloadRTL.cpp.o
9.574 [68/18/890] Building CXX object offload/libomptarget/CMakeFiles/omptarget.dir/OpenMP/InteropAPI.cpp.o
9.621 [68/17/891] Building CXX object offload/libomptarget/CMakeFiles/omptarget.dir/device.cpp.o
9.875 [68/16/892] Building CXX object offload/libomptarget/CMakeFiles/omptarget.dir/OpenMP/Mapping.cpp.o
9.943 [68/15/893] Building CXX object compiler-rt/lib/asan/CMakeFiles/RTAsan_dynamic.x86_64.dir/asan_interceptors.cpp.o
9.988 [68/14/894] Building CXX object offload/libomptarget/CMakeFiles/omptarget.dir/OpenMP/API.cpp.o
10.065 [68/13/895] Building CXX object offload/libomptarget/CMakeFiles/omptarget.dir/interface.cpp.o
10.377 [68/12/896] Building CXX object compiler-rt/lib/asan/CMakeFiles/RTAsan.x86_64.dir/asan_interceptors.cpp.o
10.432 [68/11/897] Building CXX object offload/libomptarget/CMakeFiles/omptarget.dir/PluginManager.cpp.o
10.498 [68/10/898] Building CXX object offload/libomptarget/CMakeFiles/omptarget.dir/omptarget.cpp.o
10.682 [68/9/899] Building CXX object offload/liboffload/CMakeFiles/LLVMOffload.dir/src/OffloadLib.cpp.o
10.863 [68/8/900] Building CXX object flang-rt/lib/runtime/CMakeFiles/flang_rt.runtime.static.dir/edit-output.cpp.o
In file included from /home/botworker/bbot/builds/openmp-offload-sles-build/llvm.src/flang-rt/lib/runtime/edit-output.cpp:10:
/home/botworker/bbot/builds/openmp-offload-sles-build/llvm.src/flang-rt/include/flang-rt/runtime/emit-encoded.h:49:40: warning: implicit conversion from 'const UnsignedChar' (aka 'const char16_t') to 'char32_t' may change the meaning of the represented code unit [-Wcharacter-conversion]
   49 |       auto len{EncodeUTF8(buffer + at, *uData++)};
      |                ~~~~~~~~~~              ^~~~~~~~
/home/botworker/bbot/builds/openmp-offload-sles-build/llvm.src/flang-rt/lib/runtime/edit-output.cpp:865:18: note: in instantiation of function template specialization 'Fortran::runtime::io::EmitEncoded<Fortran::runtime::io::IoStatementState, char16_t, true>' requested here
  865 |       ok = ok && EmitEncoded(io, &ch, 1);
      |                  ^

```

</details>

https://github.com/llvm/llvm-project/pull/140569