Tweak output of const panic diagnostic by estebank · Pull Request #136503 · rust-lang/rust

estebank · 2025-02-03T19:48:26Z

Shorten span of panic failures in const context

Previously, we included a redundant prefix on the panic message and a postfix of the location of the panic. The prefix didn't carry any additional information beyond "something failed", and the location of the panic is redundant with the diagnostic's span, which gets printed out even if its code is not shown.

error[E0080]: evaluation of constant value failed
--> $DIR/assert-type-intrinsics.rs:11:9
   |
LL |         MaybeUninit::<!>::uninit().assume_init();
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ panic: aborted execution: attempted to instantiate uninhabited type `!`

error[E0080]: evaluation of `Fail::<i32>::C` failed
--> $DIR/collect-in-dead-closure.rs:9:19
   |
LL |     const C: () = panic!();
   |                   ^^^^^^^^ explicit panic
   |
   = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0080]: evaluation of constant value failed
--> $DIR/uninhabited.rs:87:9
   |
LL |         assert!(false);
   |         ^^^^^^^^^^^^^^ assertion failed: false
   |
   = note: this error originates in the macro `assert` (in Nightly builds, run with -Z macro-backtrace for more info)

Remove duplicated span from const eval frame list

When the primary span for a const error is the same as the first frame in the const error report, skip it.

error[E0080]: evaluation of constant value failed
  --> $DIR/issue-88434-removal-index-should-be-less.rs:3:24
   |
LL | const _CONST: &[u8] = &f(&[], |_| {});
   |                        ^^^^^^^^^^^^^^ explicit panic
   |
note: inside `f::<{closure@$DIR/issue-88434-removal-index-should-be-less.rs:3:31: 3:34}>`
  --> $DIR/issue-88434-removal-index-should-be-less.rs:10:5
   |
LL |     panic!()
   |     ^^^^^^^^ the failure occurred here
   = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info)

instead of

error[E0080]: evaluation of constant value failed
--> $DIR/issue-88434-removal-index-should-be-less.rs:10:5
   |
LL |     panic!()
   |     ^^^^^^^^ explicit panic
   |
note: inside `f::<{closure@$DIR/issue-88434-removal-index-should-be-less.rs:3:31: 3:34}>`
--> $DIR/issue-88434-removal-index-should-be-less.rs:10:5
   |
LL |     panic!()
   |     ^^^^^^^^
note: inside `_CONST`
--> $DIR/issue-88434-removal-index-should-be-less.rs:3:24
   |
LL | const _CONST: &[u8] = &f(&[], |_| {});
   |                        ^^^^^^^^^^^^^^
   = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info)

note: erroneous constant encountered
--> $DIR/issue-88434-removal-index-should-be-less.rs:3:23
   |
LL | const _CONST: &[u8] = &f(&[], |_| {});
   |                       ^^^^^^^^^^^^^^^

r? @oli-obk

rustbot · 2025-02-03T19:48:36Z

Some changes occurred to the CTFE machinery

cc @rust-lang/wg-const-eval

The Miri subtree was changed

cc @rust-lang/miri

tests/ui/borrowck/issue-81899.stderr

tests/ui/consts/const-eval/const_panic.stderr

rustbot · 2025-02-04T02:38:45Z

Some changes occurred to the CTFE / Miri interpreter

cc @rust-lang/miri

tests/ui/borrowck/issue-88434-removal-index-should-be-less.stderr

estebank · 2025-02-05T17:59:34Z

I reverted the "inside" -> "called from" wording change purely to ease on the review of this PR. I think it'd be nicer on the reviewer if we split off that change to its own PR with fewer moving parts.

tests/ui/infinite/infinite-recursion-const-fn.stderr

compiler/rustc_const_eval/src/const_eval/error.rs

compiler/rustc_const_eval/src/interpret/stack.rs

tests/ui/const-generics/issues/issue-100313.rs

RalfJung · 2025-02-07T07:45:45Z

tests/ui/consts/const-eval/const_fn_ptr_fail2.rs

(not new in your PR) why is this not in the "miri unleashes" folder...?

tests/ui/consts/const-eval/raw-pointer-ub.stderr

tests/ui/consts/const-eval/transmute-size-mismatch.rs

tests/ui/const-generics/issues/issue-100313.stderr

compiler/rustc_const_eval/src/const_eval/error.rs

bors · 2025-02-23T05:50:40Z

☔ The latest upstream changes (presumably #137446) made this pull request unmergeable. Please resolve the merge conflicts.

oli-obk · 2025-02-25T03:20:58Z

r? @RalfJung

RalfJung

Thanks for the patience, I like the new output! We can keep discussing further changes to the format if you want in some issue, but meanwhile we can land this as a strict improvement. I just have some nits.

@rustbot author

tests/ui/const-ptr/forbidden_slices.stderr

tests/ui/consts/const-eval/heap/alloc_intrinsic_errors.rs

tests/ui/consts/const-eval/unwind-abort.rs

tests/ui/consts/const-eval/validate_uninhabited_zsts.rs

compiler/rustc_const_eval/src/const_eval/error.rs

RalfJung · 2025-02-28T07:06:05Z

Thanks! r=me with the final nit resolved, and the commits squashed.

Previously, we included a redundant prefix on the panic message and a postfix of the location of the panic. The prefix didn't carry any additional information beyond "something failed", and the location of the panic is redundant with the diagnostic's span, which gets printed out even if its code is not shown. ``` error[E0080]: evaluation of constant value failed --> $DIR/assert-type-intrinsics.rs:11:9 | LL | MaybeUninit::<!>::uninit().assume_init(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ evaluation panicked: aborted execution: attempted to instantiate uninhabited type `!` ``` ``` error[E0080]: evaluation of `Fail::<i32>::C` failed --> $DIR/collect-in-dead-closure.rs:9:19 | LL | const C: () = panic!(); | ^^^^^^^^ evaluation panicked: explicit panic | = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info) ``` ``` error[E0080]: evaluation of constant value failed --> $DIR/uninhabited.rs:41:9 | LL | assert!(false); | ^^^^^^^^^^^^^^ evaluation panicked: assertion failed: false | = note: this error originates in the macro `assert` (in Nightly builds, run with -Z macro-backtrace for more info) ``` --- When the primary span for a const error is the same as the first frame in the const error report, skip it. ``` error[E0080]: evaluation of constant value failed --> $DIR/issue-88434-removal-index-should-be-less.rs:3:24 | LL | const _CONST: &[u8] = &f(&[], |_| {}); | ^^^^^^^^^^^^^^ evaluation panicked: explicit panic | note: inside `f::<{closure@$DIR/issue-88434-removal-index-should-be-less.rs:3:31: 3:34}>` --> $DIR/issue-88434-removal-index-should-be-less.rs:10:5 | LL | panic!() | ^^^^^^^^ the failure occurred here = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info) ``` instead of ``` error[E0080]: evaluation of constant value failed --> $DIR/issue-88434-removal-index-should-be-less.rs:10:5 | LL | panic!() | ^^^^^^^^ explicit panic | note: inside `f::<{closure@$DIR/issue-88434-removal-index-should-be-less.rs:3:31: 3:34}>` --> $DIR/issue-88434-removal-index-should-be-less.rs:10:5 | LL | panic!() | ^^^^^^^^ note: inside `_CONST` --> $DIR/issue-88434-removal-index-should-be-less.rs:3:24 | LL | const _CONST: &[u8] = &f(&[], |_| {}); | ^^^^^^^^^^^^^^ = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info) ``` --- Revert order of constant evaluation errors Point at the code the user wrote first and std functions last. ``` error[E0080]: evaluation of constant value failed --> $DIR/const-errs-dont-conflict-103369.rs:5:25 | LL | impl ConstGenericTrait<{my_fn(1)}> for () {} | ^^^^^^^^ evaluation panicked: Some error occurred | note: called from `my_fn` --> $DIR/const-errs-dont-conflict-103369.rs:10:5 | LL | panic!("Some error occurred"); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info) ``` instead of ``` error[E0080]: evaluation of constant value failed --> $DIR/const-errs-dont-conflict-103369.rs:10:5 | LL | panic!("Some error occurred"); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Some error occurred | note: called from `<() as ConstGenericTrait<{my_fn(1)}>>::{constant#0}` --> $DIR/const-errs-dont-conflict-103369.rs:5:25 | LL | impl ConstGenericTrait<{my_fn(1)}> for () {} | ^^^^^^^^ = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info) ```

estebank · 2025-02-28T21:23:07Z

@bors r=RalfJung

bors · 2025-02-28T21:23:09Z

📌 Commit 7d4d09e has been approved by RalfJung

It is now in the queue for this repository.

Tweak output of const panic diagnostic ### Shorten span of panic failures in const context Previously, we included a redundant prefix on the panic message and a postfix of the location of the panic. The prefix didn't carry any additional information beyond "something failed", and the location of the panic is redundant with the diagnostic's span, which gets printed out even if its code is not shown. ``` error[E0080]: evaluation of constant value failed --> $DIR/assert-type-intrinsics.rs:11:9 | LL | MaybeUninit::<!>::uninit().assume_init(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ panic: aborted execution: attempted to instantiate uninhabited type `!` ``` ``` error[E0080]: evaluation of `Fail::<i32>::C` failed --> $DIR/collect-in-dead-closure.rs:9:19 | LL | const C: () = panic!(); | ^^^^^^^^ explicit panic | = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info) ``` ``` error[E0080]: evaluation of constant value failed --> $DIR/uninhabited.rs:87:9 | LL | assert!(false); | ^^^^^^^^^^^^^^ assertion failed: false | = note: this error originates in the macro `assert` (in Nightly builds, run with -Z macro-backtrace for more info) ``` ### Remove duplicated span from const eval frame list When the primary span for a const error is the same as the first frame in the const error report, skip it. ``` error[E0080]: evaluation of constant value failed --> $DIR/issue-88434-removal-index-should-be-less.rs:3:24 | LL | const _CONST: &[u8] = &f(&[], |_| {}); | ^^^^^^^^^^^^^^ explicit panic | note: inside `f::<{closure@$DIR/issue-88434-removal-index-should-be-less.rs:3:31: 3:34}>` --> $DIR/issue-88434-removal-index-should-be-less.rs:10:5 | LL | panic!() | ^^^^^^^^ the failure occurred here = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info) ``` instead of ``` error[E0080]: evaluation of constant value failed --> $DIR/issue-88434-removal-index-should-be-less.rs:10:5 | LL | panic!() | ^^^^^^^^ explicit panic | note: inside `f::<{closure@$DIR/issue-88434-removal-index-should-be-less.rs:3:31: 3:34}>` --> $DIR/issue-88434-removal-index-should-be-less.rs:10:5 | LL | panic!() | ^^^^^^^^ note: inside `_CONST` --> $DIR/issue-88434-removal-index-should-be-less.rs:3:24 | LL | const _CONST: &[u8] = &f(&[], |_| {}); | ^^^^^^^^^^^^^^ = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info) note: erroneous constant encountered --> $DIR/issue-88434-removal-index-should-be-less.rs:3:23 | LL | const _CONST: &[u8] = &f(&[], |_| {}); | ^^^^^^^^^^^^^^^ ``` r? `@oli-obk`

…iaskrgr Rollup of 8 pull requests Successful merges: - rust-lang#136503 (Tweak output of const panic diagnostic) - rust-lang#137390 (tests: fix up new test for nocapture -> capture(none) change) - rust-lang#137617 (Introduce `feature(generic_const_parameter_types)`) - rust-lang#137719 (Add missing case explanation for doc inlined re-export of doc hidden item) - rust-lang#137763 (Use `mk_ty_from_kind` a bit less, clean up lifetime handling in borrowck) - rust-lang#137769 (Do not yeet `unsafe<>` from type when formatting unsafe binder) - rust-lang#137776 (Some `rustc_transmute` cleanups) - rust-lang#137800 (Remove `ParamEnv::without_caller_bounds`) r? `@ghost` `@rustbot` modify labels: rollup

Rollup merge of rust-lang#136503 - estebank:const-panic, r=RalfJung Tweak output of const panic diagnostic ### Shorten span of panic failures in const context Previously, we included a redundant prefix on the panic message and a postfix of the location of the panic. The prefix didn't carry any additional information beyond "something failed", and the location of the panic is redundant with the diagnostic's span, which gets printed out even if its code is not shown. ``` error[E0080]: evaluation of constant value failed --> $DIR/assert-type-intrinsics.rs:11:9 | LL | MaybeUninit::<!>::uninit().assume_init(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ panic: aborted execution: attempted to instantiate uninhabited type `!` ``` ``` error[E0080]: evaluation of `Fail::<i32>::C` failed --> $DIR/collect-in-dead-closure.rs:9:19 | LL | const C: () = panic!(); | ^^^^^^^^ explicit panic | = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info) ``` ``` error[E0080]: evaluation of constant value failed --> $DIR/uninhabited.rs:87:9 | LL | assert!(false); | ^^^^^^^^^^^^^^ assertion failed: false | = note: this error originates in the macro `assert` (in Nightly builds, run with -Z macro-backtrace for more info) ``` ### Remove duplicated span from const eval frame list When the primary span for a const error is the same as the first frame in the const error report, skip it. ``` error[E0080]: evaluation of constant value failed --> $DIR/issue-88434-removal-index-should-be-less.rs:3:24 | LL | const _CONST: &[u8] = &f(&[], |_| {}); | ^^^^^^^^^^^^^^ explicit panic | note: inside `f::<{closure@$DIR/issue-88434-removal-index-should-be-less.rs:3:31: 3:34}>` --> $DIR/issue-88434-removal-index-should-be-less.rs:10:5 | LL | panic!() | ^^^^^^^^ the failure occurred here = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info) ``` instead of ``` error[E0080]: evaluation of constant value failed --> $DIR/issue-88434-removal-index-should-be-less.rs:10:5 | LL | panic!() | ^^^^^^^^ explicit panic | note: inside `f::<{closure@$DIR/issue-88434-removal-index-should-be-less.rs:3:31: 3:34}>` --> $DIR/issue-88434-removal-index-should-be-less.rs:10:5 | LL | panic!() | ^^^^^^^^ note: inside `_CONST` --> $DIR/issue-88434-removal-index-should-be-less.rs:3:24 | LL | const _CONST: &[u8] = &f(&[], |_| {}); | ^^^^^^^^^^^^^^ = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info) note: erroneous constant encountered --> $DIR/issue-88434-removal-index-should-be-less.rs:3:23 | LL | const _CONST: &[u8] = &f(&[], |_| {}); | ^^^^^^^^^^^^^^^ ``` r? ``@oli-obk``

The error text changed in Rust 1.87: rust-lang/rust#136503

rustbot assigned oli-obk Feb 3, 2025

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 Feb 3, 2025

RalfJung reviewed Feb 3, 2025

View reviewed changes

tests/ui/borrowck/issue-81899.stderr Outdated Show resolved Hide resolved

RalfJung reviewed Feb 3, 2025

View reviewed changes

tests/ui/consts/const-eval/const_panic.stderr Outdated Show resolved Hide resolved

estebank commented Feb 4, 2025

View reviewed changes

tests/ui/borrowck/issue-88434-removal-index-should-be-less.stderr Outdated Show resolved Hide resolved

estebank force-pushed the const-panic branch from c04532c to 64a7ed3 Compare February 4, 2025 02:52

This comment has been minimized.

Sign in to view

estebank force-pushed the const-panic branch from df621da to fad5cc6 Compare February 5, 2025 17:58

estebank commented Feb 5, 2025

View reviewed changes

tests/ui/infinite/infinite-recursion-const-fn.stderr Show resolved Hide resolved

RalfJung reviewed Feb 7, 2025

View reviewed changes

estebank force-pushed the const-panic branch 5 times, most recently from cc0f446 to 5017674 Compare February 21, 2025 19:34

RalfJung reviewed Feb 22, 2025

View reviewed changes

compiler/rustc_const_eval/src/const_eval/error.rs Outdated Show resolved Hide resolved

estebank force-pushed the const-panic branch from 5017674 to a6e43ad Compare February 25, 2025 03:02

RalfJung reviewed Feb 27, 2025

View reviewed changes

rustbot added S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Feb 27, 2025

estebank force-pushed the const-panic branch from a6e43ad to 1069039 Compare February 28, 2025 01:46

estebank 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 28, 2025

estebank mentioned this pull request Feb 28, 2025

Confusing diagnostic from const eval when offsetting a pointer out of bounds #93881

Closed

RalfJung reviewed Feb 28, 2025

View reviewed changes

compiler/rustc_const_eval/src/const_eval/error.rs Show resolved Hide resolved

estebank force-pushed the const-panic branch from 927ce61 to 7d4d09e Compare February 28, 2025 16:28

bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Feb 28, 2025

oli-obk assigned RalfJung and unassigned oli-obk Feb 28, 2025

This was referenced Mar 1, 2025

Rollup of 9 pull requests #137839

Closed

Rollup of 8 pull requests #137848

Merged

bors merged commit f012947 into rust-lang:master Mar 1, 2025
6 checks passed

rustbot added this to the 1.87.0 milestone Mar 1, 2025

nicholasbishop added a commit to google/gpt-disk-rs that referenced this pull request May 18, 2025

uguid: Fix compilation tests for guid macro

6095c1c

The error text changed in Rust 1.87: rust-lang/rust#136503

nicholasbishop mentioned this pull request May 18, 2025

uguid: Fix compilation tests for guid macro google/gpt-disk-rs#287

Merged

nicholasbishop added a commit to google/gpt-disk-rs that referenced this pull request Jun 9, 2025

uguid: Fix compilation tests for guid macro

5885eaa

The error text changed in Rust 1.87: rust-lang/rust#136503

Uh oh!

Conversation

estebank commented Feb 3, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Shorten span of panic failures in const context

Remove duplicated span from const eval frame list

Uh oh!

rustbot commented Feb 3, 2025

Uh oh!

Uh oh!

Uh oh!

rustbot commented Feb 4, 2025

Uh oh!

Uh oh!

This comment has been minimized.

estebank commented Feb 5, 2025

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

RalfJung Feb 7, 2025

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

bors commented Feb 23, 2025

Uh oh!

oli-obk commented Feb 25, 2025

Uh oh!

RalfJung left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

RalfJung commented Feb 28, 2025

Uh oh!

estebank commented Feb 28, 2025

Uh oh!

bors commented Feb 28, 2025

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

6 participants

estebank commented Feb 3, 2025 •

edited

Loading