remove -fsized-deallocation when build with clang-cl.

[Jackie9527]

Build o3de with VS2022 and clang-cl, clang-cl doesn't support -fsized-deallocation.

clang-cl, as follows:

clang --version
clang version 15.0.1
Target: x86_64-pc-windows-msvc
Thread model: posix

Script as follows:

set SRC_ROOT=E:\CODE\o3de
cmake -B %SRC_ROOT%\build\windows_clang ^
    -S %SRC_ROOT% ^
    -T ClangCl ^
    -DLY_UNITY_BUILD=ON ^
    -DLY_3RDPARTY_PATH=D:\CODE\o3de\3rd-packages ^
    -DLY_PROJECTS=AutomatedTesting

[lemonade-dm]

MSVC is the compiler, not the OS of Windows.

So this if condition is always TRUE.
This needs check that the CMAKE_SYSTEM_NAME is not "Windows"

[Jackie9527]

On Windows platform, build o3de within vcvarsall.bat

• using clang-cl, as follows:

cmake -B %SRC_ROOT%\build\windows_clang ^
    -S %SRC_ROOT% ^
    -T ClangCl ^
    ... // something else

CMAKE_CXX_COMPILER_ID is Clang and MSVC is not set.

• using cl, as follows:

cmake -B %SRC_ROOT%\build\windows_clang ^
    -S %SRC_ROOT% ^
    -G "Visual Studio 17" ^
    ... // something else

MSVC is set.

As said, clang-cl shipped with VS2022 dose not support -fsized-deallocation.
When building o3de using clang-cl, clang-cl complains unknown options about -fsized-deallocation.

[lemonade-dm]

On Windows platform, build o3de within vcvarsall.bat

* using clang-cl, as follows:

cmake -B %SRC_ROOT%\build\windows_clang ^
    -S %SRC_ROOT% ^
    -T ClangCl ^
    ... // something else

CMAKE_CXX_COMPILER_ID is Clang and MSVC is not set.

If MSVC is not set then the check of NOT MSVC would succeed and add the -fsized-deallocation option to clang-cl.

[Jackie9527]

sorry, I made a mistake.

using clang-cl, as follows, CMAKE_CXX_COMPILER_ID is Clang and MSVC is set.

cmake -B %SRC_ROOT%\build\windows_clang ^
    -S %SRC_ROOT% ^
    -T ClangCl ^
    ... // something else

[lemonade-dm]

When using Windows clang++ and clangcompilers with CMake, it doesn't set the MSVC option. Only the Windowsclang-cl` compiler sets the MSVC option

Checking against OS of Windows might be safer via comparing the CMAKE_SYSTEM_NAME variable against the string of "Windows".

CMakeLists.txt

cmake_minimum_required(VERSION 3.21)

project(test_project C CXX)

set(CMAKE_CXX_STANDARD 17)

add_executable(test_project src/main.cpp)
target_compile_options(test_project PRIVATE "-fsized-deallocation")

install(TARGETS test_project)

message(STATUS "CMAKE_CXX_COMPILER_ID is ${CMAKE_CXX_COMPILER_ID}")
message(STATUS "The MSVC option is set to ${MSVC}")

cmd

C:\Users\lumberyard-employee-dm\source\repos\test_project>cmake -B build\windows-clang -S . -G"Ninja Multi-Config" -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++
-- The C compiler identification is Clang 15.0.2 with GNU-like command-line
-- The CXX compiler identification is Clang 15.0.2 with GNU-like command-line
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working C compiler: C:/Program Files/LLVM/bin/clang.exe - skipped
-- Detecting C compile features
-- Detecting C compile features - done
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: C:/Program Files/LLVM/bin/clang++.exe - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- CMAKE_CXX_COMPILER_ID is Clang
-- The MSVC option is set to
-- Configuring done
-- Generating done
-- Build files have been written to: C:/Users/lumberyard-employee-dm/source/repos/test_project/build/windows-clang

C:\Users\lumberyard-employee-dm\source\repos\test_project>cmake -B build\windows-clang -S . -G"Ninja Multi-Config" -DCMAKE_C_COMPILER=clang-cl -DCMAKE_CXX_COMPILER=clang-cl
-- The C compiler identification is Clang 15.0.2 with MSVC-like command-line
-- The CXX compiler identification is Clang 15.0.2 with MSVC-like command-line
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working C compiler: C:/Program Files/LLVM/bin/clang-cl.exe - skipped
-- Detecting C compile features
-- Detecting C compile features - done
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: C:/Program Files/LLVM/bin/clang-cl.exe - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- CMAKE_CXX_COMPILER_ID is Clang
-- The MSVC option is set to 1
-- Configuring done
-- Generating done
-- Build files have been written to: C:/Users/lumberyard-employee-dm/source/repos/test_project/build/windows-clang

[lemonade-dm]

It looks like the clang++.exe and clang.exe on Windows supports the -fsized-allocation option.
It is just the clang-cl executable that doesn't support the option.

C:\Users\lumberyard-employee-dm\source\repos\test_project>cmake --build build\windows-clang
[1/2] Building CXX object CMakeFiles\test_project.dir\Debug\src\main.cpp.obj
clang-cl: warning: unknown argument ignored in clang-cl: '-fsized-deallocation' [-Wunknown-argument]
[2/2] Linking CXX executable Debug\test_project.exe

C:\Users\lumberyard-employee-dm\source\repos\test_project>cmake -B build\windows-clang -S . -G"Ninja Multi-Config" -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++
-- The C compiler identification is Clang 15.0.2 with GNU-like command-line
-- The CXX compiler identification is Clang 15.0.2 with GNU-like command-line
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working C compiler: C:/Program Files/LLVM/bin/clang.exe - skipped
-- Detecting C compile features
-- Detecting C compile features - done
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: C:/Program Files/LLVM/bin/clang++.exe - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- CMAKE_CXX_COMPILER_ID is Clang
-- The MSVC option is set to
-- Configuring done
-- Generating done
-- Build files have been written to: C:/Users/lumberyard-employee-dm/source/repos/test_project/build/windows-clang

C:\Users\lumberyard-employee-dm\source\repos\test_project>cmake --build build\windows-clang
[2/2] Linking CXX executable Debug\test_project.exe

[Jackie9527]

Yes, indeed.

[burelc-amzn]

Maybe we should enable the associated flag on MSVC?

Suggested change

	if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
	target_compile_options(3rdParty::pybind11 INTERFACE -fsized-deallocation)
	if(NOT MSVC)
	target_compile_options(3rdParty::pybind11 INTERFACE -fsized-deallocation)
	endif()
	endif()
	if (MSVC)
	target_compile_options(3rdParty::pybind11 INTERFACE /Zc:sizedDealloc)
	elseif ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
	target_compile_options(3rdParty::pybind11 INTERFACE -fsized-deallocation)
	endif()

[Jackie9527]

done