Fix linker error by resolving regions for main return type obligations by xonx4l · Pull Request #151377 · rust-lang/rust

xonx4l · 2026-01-19T18:02:13Z

This PR fix linker error by resolving regions for main return type obligations as discussed in #148421

Added a final check . Now the compiler double-checks the lifetimes for main right away. If they don't work it stops and gives the user a clean compiler error instead of a linker crash.

rustbot · 2026-01-19T18:02:18Z

r? @fee1-dead

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xonx4l · 2026-01-19T18:10:53Z

compiler/rustc_hir_analysis/src/check/entry.rs

+        }
+
+        let region_errors =
+            infcx.resolve_regions(main_diagnostics_def_id, param_env, tcx.mk_type_list(&[]));


One thing I'm slightly unsure about is the diagnostic span main_diagnostics_def_id as this points to the function as a whole.

This DefId is the context in which we're emitting the errors, so it should be the DefId of the whole body. This is correct. Please use ty::List::empty() instead of mk_type_list

Also, can you change this function to return Result<(), ErrorGuaranteed> and instead of using error = true just return Err(guar).

We shouldn't emit region errors if there are fulfillment errors

@lcnr sorry I was a bit busy . I have made the the changes you asked for . Thanks!

compiler/rustc_hir_analysis/src/check/entry.rs

rustbot · 2026-01-22T17:32:10Z

Reminder, once the PR becomes ready for a review, use @rustbot ready.

xonx4l · 2026-02-07T17:14:21Z

@rustbot ready

fee1-dead · 2026-02-17T00:52:24Z

Overall looks correct, but for signoff:

r? lcnr

xonx4l · 2026-02-23T14:51:49Z

@rustbot ready

lcnr · 2026-03-02T09:21:57Z

compiler/rustc_hir_analysis/src/check/entry.rs


    if error {
-        return;
+        return Ok(());


?

we should return Err(ErrorGuaranteed) here

I am sorry I got a bit busy and it just slipped out of my focus . Updated to enforce Err(ErrorGuaranteed). Thanks !

lcnr · 2026-03-02T09:22:10Z

compiler/rustc_hir_analysis/src/check/entry.rs

    .is_err()
    {
-        return;
+        return Ok(());


rustbot · 2026-03-24T04:57:56Z

This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.

lcnr · 2026-03-24T10:30:48Z

compiler/rustc_hir_analysis/src/check/wfcheck.rs

            .and(items.par_opaques(|item| tcx.ensure_result().check_well_formed(item)));
-    super::entry::check_for_entry_fn(tcx);
+
+    super::entry::check_for_entry_fn(tcx)?;


why not part of the and 🤔

I kept it separate to make sure error is propagated.

lcnr · 2026-03-24T10:31:16Z

tests/ui/typeck/main-termination-lifetime-issue-148421.rs

@@ -0,0 +1,15 @@
+// check-fail


check-fail isn't necessary.

Can you add a comment for what this is testing (and link to the issue in the file (and not necessarily in the test name))

Okay will add.

rustbot assigned fee1-dead Jan 19, 2026

rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels Jan 19, 2026

xonx4l commented Jan 19, 2026

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fee1-dead requested changes Jan 22, 2026

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rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. and removed S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. labels Feb 7, 2026

theemathas mentioned this pull request Feb 11, 2026

#![feature(trivial_bounds)] incorrectly suggested, and then causing linker errors on Windows #128682

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rustbot assigned lcnr and unassigned fee1-dead Feb 17, 2026

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xonx4l force-pushed the main_termination branch from ddf220c to 48c7506 Compare February 21, 2026 08:57

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lcnr reviewed Mar 2, 2026

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compiler/rustc_hir_analysis/src/check/entry.rs Outdated

.is_err()

{

return;

return Ok(());

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and here

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xonx4l and others added 5 commits March 19, 2026 13:10

main-termination

3abd180

moving test files

884e340

remove duplicated content

25506dc

bless test

b516062

use ErrorGuaranteed

ce665cd

xonx4l force-pushed the main_termination branch from 48c7506 to ce665cd Compare March 24, 2026 04:57

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Enforce Err(ErrorGuaranteed)

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lcnr reviewed Mar 24, 2026

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xonx4l commented Feb 7, 2026

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xonx4l commented Feb 23, 2026

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xonx4l Mar 26, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

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xonx4l Mar 26, 2026 •

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