[llvm] Remove dependence on <ciso646> (PR #73273)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-ppc64le-rhel` running on `ppc64le-clang-rhel-test` while building `llvm` at step 5 "build-unified-tree".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/145/builds/5017

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

```
Step 5 (build-unified-tree) failure: build (failure)
1.712 [4846/58/1] Generating VCSRevision.h
3.353 [4846/57/2] Building CXX object tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/ClangOpenCLBuiltinEmitter.cpp.o
FAILED: tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/ClangOpenCLBuiltinEmitter.cpp.o 
ccache /home/buildbots/llvm-external-buildbots/clang.19.1.7/bin/clang++ --gcc-toolchain=/gcc-toolchain/usr -DCLANG_EXPORTS -DGTEST_HAS_RTTI=0 -DLLVM_BUILD_STATIC -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/build/tools/clang/utils/TableGen -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/utils/TableGen -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/include -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/build/tools/clang/include -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/build/include -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror -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 -ffunction-sections -fdata-sections -fno-common -Woverloaded-virtual -Wno-nested-anon-types -O3 -DNDEBUG -std=c++17  -fno-exceptions -funwind-tables -fno-rtti -UNDEBUG -MD -MT tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/ClangOpenCLBuiltinEmitter.cpp.o -MF tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/ClangOpenCLBuiltinEmitter.cpp.o.d -o tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/ClangOpenCLBuiltinEmitter.cpp.o -c /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/utils/TableGen/ClangOpenCLBuiltinEmitter.cpp
In file included from /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/utils/TableGen/ClangOpenCLBuiltinEmitter.cpp:28:
In file included from /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include/llvm/TableGen/Record.h:28:
In file included from /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include/llvm/Support/Timer.h:15:
In file included from /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include/llvm/Support/Mutex.h:16:
/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include/llvm/Support/Threading.h:22:10: fatal error: 'version' file not found
   22 | #include <version>
      |          ^~~~~~~~~
1 error generated.
3.390 [4846/56/3] Building CXX object tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/ClangCommentCommandInfoEmitter.cpp.o
FAILED: tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/ClangCommentCommandInfoEmitter.cpp.o 
ccache /home/buildbots/llvm-external-buildbots/clang.19.1.7/bin/clang++ --gcc-toolchain=/gcc-toolchain/usr -DCLANG_EXPORTS -DGTEST_HAS_RTTI=0 -DLLVM_BUILD_STATIC -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/build/tools/clang/utils/TableGen -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/utils/TableGen -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/include -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/build/tools/clang/include -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/build/include -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror -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 -ffunction-sections -fdata-sections -fno-common -Woverloaded-virtual -Wno-nested-anon-types -O3 -DNDEBUG -std=c++17  -fno-exceptions -funwind-tables -fno-rtti -UNDEBUG -MD -MT tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/ClangCommentCommandInfoEmitter.cpp.o -MF tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/ClangCommentCommandInfoEmitter.cpp.o.d -o tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/ClangCommentCommandInfoEmitter.cpp.o -c /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/utils/TableGen/ClangCommentCommandInfoEmitter.cpp
In file included from /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/utils/TableGen/ClangCommentCommandInfoEmitter.cpp:16:
In file included from /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include/llvm/TableGen/Record.h:28:
In file included from /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include/llvm/Support/Timer.h:15:
In file included from /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include/llvm/Support/Mutex.h:16:
/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include/llvm/Support/Threading.h:22:10: fatal error: 'version' file not found
   22 | #include <version>
      |          ^~~~~~~~~
1 error generated.
3.403 [4846/55/4] Building CXX object tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/ClangDiagnosticsEmitter.cpp.o
FAILED: tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/ClangDiagnosticsEmitter.cpp.o 
ccache /home/buildbots/llvm-external-buildbots/clang.19.1.7/bin/clang++ --gcc-toolchain=/gcc-toolchain/usr -DCLANG_EXPORTS -DGTEST_HAS_RTTI=0 -DLLVM_BUILD_STATIC -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/build/tools/clang/utils/TableGen -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/utils/TableGen -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/include -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/build/tools/clang/include -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/build/include -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror -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 -ffunction-sections -fdata-sections -fno-common -Woverloaded-virtual -Wno-nested-anon-types -O3 -DNDEBUG -std=c++17  -fno-exceptions -funwind-tables -fno-rtti -UNDEBUG -MD -MT tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/ClangDiagnosticsEmitter.cpp.o -MF tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/ClangDiagnosticsEmitter.cpp.o.d -o tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/ClangDiagnosticsEmitter.cpp.o -c /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/utils/TableGen/ClangDiagnosticsEmitter.cpp
In file included from /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/utils/TableGen/ClangDiagnosticsEmitter.cpp:24:
In file included from /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include/llvm/TableGen/Record.h:28:
In file included from /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include/llvm/Support/Timer.h:15:
In file included from /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include/llvm/Support/Mutex.h:16:
/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include/llvm/Support/Threading.h:22:10: fatal error: 'version' file not found
   22 | #include <version>
      |          ^~~~~~~~~
1 error generated.
3.424 [4846/54/5] Building CXX object tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/ClangTypeNodesEmitter.cpp.o
FAILED: tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/ClangTypeNodesEmitter.cpp.o 
ccache /home/buildbots/llvm-external-buildbots/clang.19.1.7/bin/clang++ --gcc-toolchain=/gcc-toolchain/usr -DCLANG_EXPORTS -DGTEST_HAS_RTTI=0 -DLLVM_BUILD_STATIC -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/build/tools/clang/utils/TableGen -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/utils/TableGen -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/include -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/build/tools/clang/include -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/build/include -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror -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 -ffunction-sections -fdata-sections -fno-common -Woverloaded-virtual -Wno-nested-anon-types -O3 -DNDEBUG -std=c++17  -fno-exceptions -funwind-tables -fno-rtti -UNDEBUG -MD -MT tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/ClangTypeNodesEmitter.cpp.o -MF tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/ClangTypeNodesEmitter.cpp.o.d -o tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/ClangTypeNodesEmitter.cpp.o -c /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/utils/TableGen/ClangTypeNodesEmitter.cpp
In file included from /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/utils/TableGen/ClangTypeNodesEmitter.cpp:48:
In file included from /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/utils/TableGen/ASTTableGen.h:12:
In file included from /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include/llvm/TableGen/Record.h:28:
In file included from /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include/llvm/Support/Timer.h:15:
In file included from /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include/llvm/Support/Mutex.h:16:
/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include/llvm/Support/Threading.h:22:10: fatal error: 'version' file not found
   22 | #include <version>
      |          ^~~~~~~~~
1 error generated.
3.486 [4846/53/6] Building CXX object tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/NeonEmitter.cpp.o
FAILED: tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/NeonEmitter.cpp.o 
ccache /home/buildbots/llvm-external-buildbots/clang.19.1.7/bin/clang++ --gcc-toolchain=/gcc-toolchain/usr -DCLANG_EXPORTS -DGTEST_HAS_RTTI=0 -DLLVM_BUILD_STATIC -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/build/tools/clang/utils/TableGen -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/utils/TableGen -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/include -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/build/tools/clang/include -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/build/include -I/home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/llvm/include -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror -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 -ffunction-sections -fdata-sections -fno-common -Woverloaded-virtual -Wno-nested-anon-types -O3 -DNDEBUG -std=c++17  -fno-exceptions -funwind-tables -fno-rtti -UNDEBUG -MD -MT tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/NeonEmitter.cpp.o -MF tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/NeonEmitter.cpp.o.d -o tools/clang/utils/TableGen/CMakeFiles/clang-tblgen.dir/NeonEmitter.cpp.o -c /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/utils/TableGen/NeonEmitter.cpp
In file included from /home/buildbots/llvm-external-buildbots/workers/ppc64le-clang-rhel-test/clang-ppc64le-rhel/llvm-project/clang/utils/TableGen/NeonEmitter.cpp:38:

```

</details>

https://github.com/llvm/llvm-project/pull/73273