How to build LLVMSPIRVLib as a shared library on Windows?

[ZzEeKkAa]

Hello there!

I've tried to build library on windows, but it seems like there is no option to build it as shared library on windows:

LLVM does not support shared libraries on windows:
https://www.llvm.org/docs/CMake.html#llvm-related-variables
And the way library is written is add_llvm_library
https://github.com/KhronosGroup/SPIRV-LLVM-Translator/blob/main/lib/SPIRV/CMakeLists.txt#L43

If I try to build it with -DLLVM_BUILD_LLVM_DYLIB=ON, I get :

[43/43] Linking CXX executable tools\llvm-spirv\llvm-spirv.exe
FAILED: tools/llvm-spirv/llvm-spirv.exe
C:\windows\system32\cmd.exe /C "cd . && C:\Users\yevhenii\.miniforge3\conda-bld\debug_1717564664836\_build_env\Library\bin\cmake.exe -E vs_link_exe --intdir=tools\llvm-spirv\CMakeFiles\llvm-spirv.dir --rc=C:\PROGRA~2\WI3CF2~1\10\bin\100226~1.0\x64\rc.exe --mt=C:\PROGRA~2\WI3CF2~1\10\bin\100226~1.0\x64\mt.exe --manifests  -- C:\PROGRA~2\MICROS~4\2022\BUILDT~1\VC\Tools\MSVC\1429~1.301\bin\HostX64\x64\link.exe /nologo @CMakeFiles\llvm-spirv.rsp  /out:tools\llvm-spirv\llvm-spirv.exe /implib:tools\llvm-spirv\llvm-spirv.lib /pdb:tools\llvm-spirv\llvm-spirv.pdb /version:0.0 /machine:x64 /STACK:10000000 /INCREMENTAL:NO /subsystem:console && cd ."
LINK: command "C:\PROGRA~2\MICROS~4\2022\BUILDT~1\VC\Tools\MSVC\1429~1.301\bin\HostX64\x64\link.exe /nologo @CMakeFiles\llvm-spirv.rsp /out:tools\llvm-spirv\llvm-spirv.exe /implib:tools\llvm-spirv\llvm-spirv.lib /pdb:tools\llvm-spirv\llvm-spirv.pdb /version:0.0 /machine:x64 /STACK:10000000 /INCREMENTAL:NO /subsystem:console /MANIFEST:EMBED,ID=1" failed (exit code 1181) with the following output:
LINK : fatal error LNK1181: cannot open input file 'lib\SPIRV\LLVMSPIRVLib.lib'
ninja: build stopped: subcommand failed.

So cmake builds library as .dll, but whenever it comes to building llvm-spirv binary it is looking for static library.

Please note, that on linux it works as expected: It creates shared library and links binary to it.

So do you have any ideas how to bypass it?

[MrSidims]

There was a patch #1543 that later was reverted, see the latest comments in the PR. If you try it on windows - would it help?

[ZzEeKkAa]

@MrSidims as far as I can understand - it does the oposit - blocks shared library build and build static library, when trying to build shared one with LLVM_LINK_LLVM_DYLIB. Moreover LLVM_LINK_LLVM_DYLIB is not supported on Windows:

LLVM_BUILD_LLVM_DYLIB:BOOL
If enabled, the target for building the libLLVM shared library is added. This library contains all of LLVM’s components in a single shared library. Defaults to OFF. This cannot be used in conjunction with BUILD_SHARED_LIBS. Tools will only be linked to the libLLVM shared library if LLVM_LINK_LLVM_DYLIB is also ON. The components in the library can be customised by setting LLVM_DYLIB_COMPONENTS to a list of the desired components. This option is not available on Windows.

https://www.llvm.org/docs/CMake.html