[SAOC 2026] MLIR support Weekly Update #3

[Asadbek]

Hello everyone,

This week was mostly spent on the CMake side of the MLIR 
integration, and it turned out to be more involved than I 
expected. LDC's build setup is a bit more complicated than I had 
realized.

My initial CMake change that adds MLIR as a dependency worked 
fine on my local machine, but it broke some targets on CI. I 
reproduced the failures locally by building the compiler the way 
the CI does. I haven't been able to fix them yet.

I had a call with Nicholas today to dig into this. We made 
progress, but we're now stuck on linker errors. When compiler is 
built with `-DLDC_LINK_MANUALLY=OFF` option, it seem to link the 
dependencies a bit differently than with 
`-DLDC_LINK_MANUALLY=ON`. On Nicholas's suggestion, I posted the 
errors and what we have tried on the draft PR [1] to get advice 
from Martin Kinkelin.

If anyone else has experience with linking MLIR/LLVM into a CMake 
project like LDC's, I would be very happy to hear your 
suggestions, either here or on the PR.

In the meantime, I will keep investigating the linker failures, 
and I'll report back next week.
Thanks to Nicholas for his help and mentoring on this.

[1] 
https://github.com/ldc-developers/ldc/pull/5295#issuecomment-6040984637