[clang] [llvm] Add macro to suppress -Wunnecessary-virtual-specifier (PR #139614)

[LLVM Continuous Integration via cfe-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `llvm-clang-x86_64-gcc-ubuntu` running on `sie-linux-worker3` while building `clang,llvm` at step 5 "build-unified-tree".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/174/builds/18128

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

```
Step 5 (build-unified-tree) failure: build (failure)
0.032 [7166/34/1] Building CXX object lib/Support/CMakeFiles/LLVMSupport.dir/ABIBreak.cpp.o
0.038 [7165/34/2] Building CXX object lib/Support/CMakeFiles/LLVMSupport.dir/COM.cpp.o
FAILED: lib/Support/CMakeFiles/LLVMSupport.dir/COM.cpp.o 
/opt/ccache/bin/g++ -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/lib/Support -I/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/lib/Support -I/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/include -I/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/include -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wno-missing-field-initializers -pedantic -Wno-long-long -Wimplicit-fallthrough -Wno-uninitialized -Wno-nonnull -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -Wno-misleading-indentation -fdiagnostics-color -ffunction-sections -fdata-sections -O3 -DNDEBUG -UNDEBUG -std=c++17  -fno-exceptions -funwind-tables -fno-rtti -MD -MT lib/Support/CMakeFiles/LLVMSupport.dir/COM.cpp.o -MF lib/Support/CMakeFiles/LLVMSupport.dir/COM.cpp.o.d -o lib/Support/CMakeFiles/LLVMSupport.dir/COM.cpp.o -c /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/lib/Support/COM.cpp
In file included from /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/include/llvm/Support/COM.h:17,
                 from /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/lib/Support/COM.cpp:13:
/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/include/llvm/Support/Compiler.h:719:40: error: missing binary operator before token "("
  719 | #if defined(__clang__) && __has_warning("-Wunnecessary-virtual-specifier")
      |                                        ^
0.069 [7165/33/3] Building CXX object lib/Support/CMakeFiles/LLVMSupport.dir/AutoConvert.cpp.o
0.483 [7165/32/4] Building CXX object lib/Support/CMakeFiles/LLVMSupport.dir/BuryPointer.cpp.o
FAILED: lib/Support/CMakeFiles/LLVMSupport.dir/BuryPointer.cpp.o 
/opt/ccache/bin/g++ -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/lib/Support -I/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/lib/Support -I/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/include -I/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/include -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wno-missing-field-initializers -pedantic -Wno-long-long -Wimplicit-fallthrough -Wno-uninitialized -Wno-nonnull -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -Wno-misleading-indentation -fdiagnostics-color -ffunction-sections -fdata-sections -O3 -DNDEBUG -UNDEBUG -std=c++17  -fno-exceptions -funwind-tables -fno-rtti -MD -MT lib/Support/CMakeFiles/LLVMSupport.dir/BuryPointer.cpp.o -MF lib/Support/CMakeFiles/LLVMSupport.dir/BuryPointer.cpp.o.d -o lib/Support/CMakeFiles/LLVMSupport.dir/BuryPointer.cpp.o -c /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/lib/Support/BuryPointer.cpp
In file included from /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/include/llvm/Support/BuryPointer.h:12,
                 from /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/lib/Support/BuryPointer.cpp:9:
/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/include/llvm/Support/Compiler.h:719:40: error: missing binary operator before token "("
  719 | #if defined(__clang__) && __has_warning("-Wunnecessary-virtual-specifier")
      |                                        ^
0.502 [7165/31/5] Building CXX object lib/Demangle/CMakeFiles/LLVMDemangle.dir/Demangle.cpp.o
0.589 [7165/30/6] Building CXX object lib/Demangle/CMakeFiles/LLVMDemangle.dir/DLangDemangle.cpp.o
0.825 [7165/29/7] Building CXX object lib/Support/CMakeFiles/LLVMSupport.dir/AArch64BuildAttributes.cpp.o
FAILED: lib/Support/CMakeFiles/LLVMSupport.dir/AArch64BuildAttributes.cpp.o 
/opt/ccache/bin/g++ -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/lib/Support -I/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/lib/Support -I/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/include -I/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/include -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wno-missing-field-initializers -pedantic -Wno-long-long -Wimplicit-fallthrough -Wno-uninitialized -Wno-nonnull -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -Wno-misleading-indentation -fdiagnostics-color -ffunction-sections -fdata-sections -O3 -DNDEBUG -UNDEBUG -std=c++17  -fno-exceptions -funwind-tables -fno-rtti -MD -MT lib/Support/CMakeFiles/LLVMSupport.dir/AArch64BuildAttributes.cpp.o -MF lib/Support/CMakeFiles/LLVMSupport.dir/AArch64BuildAttributes.cpp.o.d -o lib/Support/CMakeFiles/LLVMSupport.dir/AArch64BuildAttributes.cpp.o -c /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/lib/Support/AArch64BuildAttributes.cpp
In file included from /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/include/llvm/ADT/STLFunctionalExtras.h:19,
                 from /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/include/llvm/ADT/StringRef.h:13,
                 from /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/include/llvm/Support/AArch64BuildAttributes.h:21,
                 from /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/lib/Support/AArch64BuildAttributes.cpp:9:
/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/include/llvm/Support/Compiler.h:719:40: error: missing binary operator before token "("
  719 | #if defined(__clang__) && __has_warning("-Wunnecessary-virtual-specifier")
      |                                        ^
0.852 [7165/28/8] Building CXX object lib/Support/CMakeFiles/LLVMSupport.dir/BlockFrequency.cpp.o
FAILED: lib/Support/CMakeFiles/LLVMSupport.dir/BlockFrequency.cpp.o 
/opt/ccache/bin/g++ -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/lib/Support -I/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/lib/Support -I/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/include -I/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/include -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wno-missing-field-initializers -pedantic -Wno-long-long -Wimplicit-fallthrough -Wno-uninitialized -Wno-nonnull -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -Wno-misleading-indentation -fdiagnostics-color -ffunction-sections -fdata-sections -O3 -DNDEBUG -UNDEBUG -std=c++17  -fno-exceptions -funwind-tables -fno-rtti -MD -MT lib/Support/CMakeFiles/LLVMSupport.dir/BlockFrequency.cpp.o -MF lib/Support/CMakeFiles/LLVMSupport.dir/BlockFrequency.cpp.o.d -o lib/Support/CMakeFiles/LLVMSupport.dir/BlockFrequency.cpp.o -c /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/lib/Support/BlockFrequency.cpp
In file included from /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/include/llvm/Support/BlockFrequency.h:16,
                 from /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/lib/Support/BlockFrequency.cpp:13:
/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/include/llvm/Support/Compiler.h:719:40: error: missing binary operator before token "("
  719 | #if defined(__clang__) && __has_warning("-Wunnecessary-virtual-specifier")
      |                                        ^
0.912 [7165/27/9] Building CXX object lib/Support/CMakeFiles/LLVMSupport.dir/circular_raw_ostream.cpp.o
FAILED: lib/Support/CMakeFiles/LLVMSupport.dir/circular_raw_ostream.cpp.o 
/opt/ccache/bin/g++ -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/lib/Support -I/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/lib/Support -I/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/include -I/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/include -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wno-missing-field-initializers -pedantic -Wno-long-long -Wimplicit-fallthrough -Wno-uninitialized -Wno-nonnull -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -Wno-misleading-indentation -fdiagnostics-color -ffunction-sections -fdata-sections -O3 -DNDEBUG -UNDEBUG -std=c++17  -fno-exceptions -funwind-tables -fno-rtti -MD -MT lib/Support/CMakeFiles/LLVMSupport.dir/circular_raw_ostream.cpp.o -MF lib/Support/CMakeFiles/LLVMSupport.dir/circular_raw_ostream.cpp.o.d -o lib/Support/CMakeFiles/LLVMSupport.dir/circular_raw_ostream.cpp.o -c /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/lib/Support/circular_raw_ostream.cpp
In file included from /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/include/llvm/ADT/SmallVector.h:18,
                 from /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/include/llvm/Support/raw_ostream.h:16,
                 from /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/include/llvm/Support/circular_raw_ostream.h:17,
                 from /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/lib/Support/circular_raw_ostream.cpp:13:
/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/include/llvm/Support/Compiler.h:719:40: error: missing binary operator before token "("
  719 | #if defined(__clang__) && __has_warning("-Wunnecessary-virtual-specifier")
      |                                        ^
0.915 [7165/26/10] Building CXX object lib/Support/CMakeFiles/LLVMSupport.dir/ARMWinEH.cpp.o
FAILED: lib/Support/CMakeFiles/LLVMSupport.dir/ARMWinEH.cpp.o 

```

</details>

https://github.com/llvm/llvm-project/pull/139614