[MSVC] LLVM failed to build when I do the cross-compiling and the target architecture is ARM64EC

[Zhaojun-Liu]

Hi: when I use msvc to cross compile LLVM, the host is amd64 and the target is ARM64EC, it failed, can you help take a look? Thanks.

Repro steps:

1. Open a VS2022 x64 command prompt
2. git clone https://github.com/llvm/llvm-project C:\gitP\llvm\llvm-project
3. mkdir C:\gitP\llvm\llvm-project\build_arm64ec & cd /d C:\gitP\llvm\llvm-project\build_arm64ec
4. cmake -G "Visual Studio 17 2022" -A ARM64EC -DCMAKE_SYSTEM_VERSION=10.0.22621.0 -DLLVM_ENABLE_PROJECTS="clang" ..\llvm
5. set VSCMD_SKIP_SENDTELEMETRY=1 & "C:\Program Files\Microsoft Visual Studio\2022\Enterprise\Common7\Tools\VsDevCmd.bat" -host_arch=amd64 -arch=arm64
6. msbuild /m /p:Platform=ARM64EC /p:Configuration=RelWithDebInfo /p:PreferredToolArchitecture=x64 LLVM.sln /t:Rebuild

follow the above steps, it failed with a lot of errors, like error MSB8066 and LLVMSupport.lib(blake3_sse41_x86-64_windows_msvc.obj) : fatal error LNK1372: hybrid map entry target function 'llvm_blake3_compress_in_place_sse41' is not 4-byte aligned , you can see the detailed log:
Build (2).log

Note:
The above results are what I added 3 lines like below before https://github.com/llvm/llvm-project/blob/main/llvm/include/llvm/DebugInfo/CodeView/CodeView.h#L76, otherwise, follow the above repro steps, it would fail due to C:\gitP\llvm\llvm-project\llvm\include\llvm\DebugInfo\CodeView\CodeView.h(137,3): error C2143: syntax error: missing '}' before 'constant', you can check the detailed logs:
Build (1).log

#if ARM64EC
#undef ARM64EC
#endif

The commit of LLVM I used is 0af448b

[efriedma-quic]

As a workaround, try passing -DLLVM_DISABLE_ASSEMBLY_FILES=ON to CMake.

[Zhaojun-Liu]

As a workaround, try passing -DLLVM_DISABLE_ASSEMBLY_FILES=ON to CMake.

Thanks for the reply. I tried to add -DLLVM_DISABLE_ASSEMBLY_FILES=ON to CMake and update msbuild command to msbuild /m:1 /p:Platform=ARM64EC /p:Configuration=RelWithDebInfo /p:PreferredToolArchitecture=x64 LLVM.sln /t:Rebuild

and a lot of 'error MSB8066', you can check the detailed log
Build_llvm_arm64ec.log

[efriedma-quic]

I think something is crashing, but I can't tell what. Maybe use /v for verbose logging? Or switch to cmake -G ninja; msbuild is generally terrible to work with.

[Zhaojun-Liu]

I think something is crashing, but I can't tell what. Maybe use /v for verbose logging? Or switch to cmake -G ninja; msbuild is generally terrible to work with.

When I tried to use Ninja, it issues: Generator Ninja does not support platform specification, but platform ARM64EC

[SaltyGlutinousRiceBall]

@Zhaojun-Liu Hello, may I ask if you have found a solution?

[Zhaojun-Liu]

@Zhaojun-Liu Hello, may I ask if you have found a solution?

No.

[SaltyGlutinousRiceBall]

@Zhaojun-Liu found the issue. CMake defines the AMD64 macro for the ARM64EC platform in the Windows-MSVC.cmake file, which caused the problem. This issue was fixed in CMake version 3.31. You can take a look at these issues.
#128992

Kitware/CMake@b2a2865

[Zhaojun-Liu]

@Zhaojun-Liu found the issue. CMake defines the AMD64 macro for the ARM64EC platform in the Windows-MSVC.cmake file, which caused the problem. This issue was fixed in CMake version 3.31. You can take a look at these issues. #128992

Kitware/CMake@b2a2865

@SaltyGlutinousRiceBall I installed cmake 3.31.6 to verify, error C2143 looks fixed, but cross-compile LLVM, it still failed with fatal error LNK1372: hybrid map entry target function 'llvm_blake3_compress_in_place_sse41' is not 4-byte aligned.

LLVM commit: 6004f55

[efriedma-quic]

As mentioned before, you can pass -DLLVM_DISABLE_ASSEMBLY_FILES=ON to disable the use of assembly files.

[Zhaojun-Liu]

As mentioned before, you can pass -DLLVM_DISABLE_ASSEMBLY_FILES=ON to disable the use of assembly files.

still failed, a lot of error MSB8066, please see the 2 log files. (I tested LLVM commit 6004f55 and 2d876ed)

Setup.log
Build.log