lld-link can't find kernel32.lib/uuid.lib...

[pawelsopensource]

Hi,
I'm trying to cross compile a simple hello-world (linux->windows) with clang-19 and getting errors from LLD linker about missing kernel32.lib/uuid.lib.

msvc/sdk files extracted from windows machine have lower/uppercase and don't match with clang/lld backend (lowercase).

./kits/10/Lib/10.0.22000.0/um/x86/kernel32.Lib
./kits/10/Lib/10.0.22000.0/um/x86/Uuid.Lib

[llvmbot]

@llvm/issue-subscribers-lld-coff

Author: Paweł Sikora (pawelsopensource)

Hi, I'm trying to cross compile a simple hello-world (linux->windows) with clang-19 and getting errors from LLD linker about missing kernel32.lib/uuid.lib.

msvc/sdk files extracted from windows machine have lower/uppercase and don't match with clang/lld backend (lowercase).

./kits/10/Lib/10.0.22000.0/um/x86/kernel32.Lib
./kits/10/Lib/10.0.22000.0/um/x86/Uuid.Lib

[MaxEW707]

If you are planning to cross-compile Win32 apps on Linux machines I highly recommend looking into https://www.brain-dump.org/projects/ciopfs/ or using symlinks to route the mis-matched case names to the case needed.

You are also going to run into a bunch of Microsoft headers with inconsistent casing as well such as Windows.h and windows.h.

[aganea]

Ciopfs is old and unmaintained. Be warned that you might into issues like this: https://issues.chromium.org/issues/40173394#comment5
If planning more long-term usage, the avenue we’ve taken at Ubisoft was to simplify having a casefold ext4 mount.

[pawelsopensource]

Ciopfs is old and unmaintained. Be warned that you might into issues like this: https://issues.chromium.org/issues/40173394#comment5 If planning more long-term usage, the avenue we’ve taken at Ubisoft was to simplify having a casefold ext4 mount.

Thanks for that hint. I'm using zfs on linux so I'll try to use a separated zfs dataset for MS/SDK with dedicated casesensitivity property.

[mstorsjo]

FWIW, when I do this, I also just set up lowercase symlinks. At http://github.com/mstorsjo/msvc-wine/, I've got one script for downloading and unpacking MSVC directly on Linux, without needing to extract files from Windows, and another script for setting up the unpacked files with lowercase symlinks, and fixing up header intra includes to refer to each other with lowercase. So despite the repo name containing -wine, it's also entirely usable without wine, just for clang-cl cross compilation.