CI build failure: missing thrust headers in CUDA 13.1.1 build

[bdice]

Description

The cpp-build CI job fails with CUDA 13.1.1 due to missing thrust header includes.

CI log: https://github.com/NVIDIA/cuopt/actions/runs/23632772472/job/68835651782#step:11:2154

Error:

$SRC_DIR/cpp/src/pdlp/termination_strategy/infeasibility_information.cu(344): error: namespace "thrust" has no member "make_transform_output_iterator"

Root Cause

infeasibility_information.cu uses thrust::make_transform_output_iterator but does not directly include thrust/iterator/transform_output_iterator.h. The symbol was previously resolved through transitive includes. An audit of the codebase shows ~45 files relying on transitive includes for various thrust symbols (make_transform_iterator, make_zip_iterator, thrust::tuple, thrust::maximum, thrust::device_ptr, thrust::transform_reduce, etc.).

[MohdAatifSiddi]

Thanks for the detailed write-up and root cause analysis, @bdice. PR #997 looks like the right approach, adding explicit includes for all 45 affected files is the correct IWYU fix and should be backward compatible with earlier CUDA toolchains since the headers already existed there (just pulled in transitively).

A couple of notes that might be worth tracking alongside or after #997:

thrust/extrema.h for thrust::maximum / thrust::minimum a few files (solution.cu, bounds_presolve.cu, compute_compatible.cu, and the load_balanced_bounds_presolve pair) use these functors and need thrust/extrema.h directly. Worth double-checking those are covered in the PR if CI is still red after the iterator headers land.

Longer-term migration as the RAPIDS ecosystem has been doing, it's worth opening a follow-up issue to migrate from thrust:: iterators/tuples to their cuda:: / cuda::std:: counterparts (cuda::std::tuple, cuda::std::pair, etc.). That insulates the codebase from future CCCL header reorganisations and aligns with the direction the broader NVIDIA ecosystem is heading.

Preventing recurrence an include-what-you-use (IWYU) CI step with a Thrust/CCCL mapping file would have caught all 45 sites before they hit the build. Could be a low-effort addition to the lint job once #997 is merged.

[rgsl888prabhu]

Thank you @bdice @MohdAatifSiddi.

@rg20 @hlinsen for viz