June 2026 Monthly report

Overview

Thanks again to Open Source Security, inc and Embecosm for their ongoing support for this project.

Project update

Thanks to the work done by Philip Herron over the last few months, gccrs now supports Generics Associated Types, a required type system feature for both compiling core and the Linux kernel. This feature required massive efforts and was a huge investment into our type system, which needed to be adapted in order for GATs to be fully supported.

We also have made major progress towards our milestone of compiling core this month, with gccrs now being able to fully macro-expand and early name-resolve the crate without erroring out or invalid behavior. We are now dealing with the remaining issues further down the compilation pipeline, and are still progressing towards our objective of being able to compile the Linux kernel in time for RustConf in September. Late name resolution issues should not prove to be too difficult, and we will spend most of our time dealing with type system issues for core. Thankfully, we have already spent a large amount of time identifying type-system issues and reducing them to test cases in our testsuite, so we are hopeful that this work will go smoothly.

In order to fully support multiple crates linking together - as is the case in most Rust projects, but especially in the Linux kernel - Pierre-Emmanuel reworked our entire metadata export and import pass and greatly improved it. Name resolution is now much stronger for multiple crates projects, and merges the results of the resolution together when importing crates. To fix an issue where certain nodes where not being exported into our metadata, as well as some of these exports being incomplete and lacking information, the pass has been moved earlier into the pipeline and now acts on our AST rather than our HIR. While we are still doing a simple and expensive export pass, it is functionally good enough and will be improved later once our main objectives are achieved.

Work on Google Summer of Code continues, with our two students Enes Cevik and Janet Chien progressing admirably on their projects. Both students are extremely productive and nice to work with, and will pass the midterm evaluation with flying colors. Thanks to them, gccrs is now much closer to handling the alloc crate, required for our objective of compiling the Linux kernel, and can also insert Drop calls for a variety of situations - required for properly running the Linux kernel compiled by gccrs. Together, Janet and Enes will bring massive improvements to the compiler over the next two months and we are grateful for their implication and involvment.

Last but not least, Zhi Heng has been working tirelessly on fixing core issues with us in order to get gccrs closer and closer to being a usable compiler. He has worked on C-styl string literals and their memory representation, as they are needed for the Linux kernel, and is now fixing an issue with the way gccrs represents wide pointers when compiling dynamically sized types. Once again, this effort is essential for gccrs to be able to properly compile the kernel and will prove to be extremely useful in the long run.

Call for contribution

• https://github.com/Rust-GCC/gccrs/issues/2500

• https://github.com/Rust-GCC/gccrs/issues/2376

Completed Activities

• gccrs: Fix type param forward declare check PR4684
• gccrs: Fix `TypePathSegmentGeneric` token collection PR4682
• gccrs: Fix `IdentifierPathPass` on sub-patterns PR4681
• gccrs: Register `global<sub>allocator</sub>` attribute PR4680
• Sync with upstream (2026-06-30): 1a2de01fbac64f97fed6f63ff655b13bff831877 PR4673
• Add size_ofval and min_alignofval intrinsics PR4672
• gccrs: turn on can_aliasall on build_pointertype PR4666
• gccrs: Fix typechecking of block expression and labels PR4665
• gccrs: Fix unify code on ADT’s to check defid PR4663
• gccrs: Fix crash when resolving invalid enum item PR4661
• backend: Fix incorrect impl block selection PR4660
• gccrs: add non_{contiguousrangeendpoints} lint PR4654
• gccrs: Create `ForeverStackBase` PR4653
• gccrs: add missing_abi lint PR4649
• gccrs: Remove `ForeverStackStore` PR4648
• gccrs: Detect errors in macro eager expansion PR4647
• gccrs: add unused visibilities lint PR4644
• gccrs: fix ICE on break with a label and a value PR4638
• gccrs: fix ICE on generic type aliases PR4637
• gccrs: add drop bounds lint PR4636
• gccrs: Add tests for local binding LIFO and nested block scopes PR4632
• gccrs: add non shorthand field patterns lint PR4628
• Add write_bytes and arith_offset PR4620
• ci: look for “<project>/<repo>#ref” pattern PR4610
• gccrs: Fix ICE when trying to resolve const expr PR4607
• gccrs: Add testcases to show gat issue is fixed PR4606
• gccrs: Add test case to show bug is fixed PR4605
• gccrs: Fix ICE when handling invalid results during monomprhization PR4604
• gccrs: Fix ICE when handling offset on types with unknown size PR4603
• backend: Refactor dynamic object fat pointers and vtable generation PR4599
• Sync with upstream (2026-06-24): 8ce473f8a26142a39487a0adac10570761f8ed90 PR4597
• Move a test into `compile/macros/mbe` PR4595
• Support GATS PR4594
• Extern crate loading improvements PR4588
• Enforce intrinsic signatures during the type checking PR4587
• gccrs: Refactor CompileDrop and add DropBuilder PR4586
• intrinsic: Add min_alignof PR4582
• Handle assert with custom message PR4581
• gccrs: Search lang_prelude when reaching module boundary during name resolution PR4580
• Fix use after move in lexer PR4579
• Workaround bugzilla PR 125600 PR4576
• Add lang owned box and box expression PR4574
• ci: prevent @noreply.github.com emails PR4573
• gccrs: Make `extern crate self` resolve to current crate PR4570
• Limit globbing visitor PR4569
• gccrs: Implement C-style string literals PR4565
• gccrs: Add Drop support for block-local variable PR4564
• Add lang item exchange_malloc PR4557
• Add allocator attrs PR4556
• Add imports to types ns PR4551
• rust: avoid ICE on attributed struct base parsing PR4514
• rust: Fix ICE with infer type used in struct attribute PR4504
• nr: Add modules to types NS PR4404

Contributors this month

• João Antunes (new contributor!)
• Enes Cevik
• Janet Chien
• Hritam Shrivastava
• Owen Avery
• Philip Herron
• Lucas Ly-Ba
• Marc Poulhiès
• Zhi Heng
• Pierre-Emmanuel Patry
• Arthur Cohen

Overall Task Status

Bugs

Test Cases

Milestones Progress

Here is the list of overarching milestones gccrs is currently targeting. We’ll use the acronym in the following milestone tables, in the column named “OA Milest.”.