Improve errors on const mismatches

[b-naber]

Fixes#86198

This allows us to suggest a correct anonymous constant in case there's a mismatch, e.g. in:

trait Trait {}
struct HasCastInTraitImpl<const N: usize, const M: usize>;
impl<const M: usize> Trait for HasCastInTraitImpl<M, { M + 1 }> {}
pub struct HasTrait<T: Trait>(T);
fn foo<const N: usize>() -> HasTrait<HasCastInTraitImpl<{ N + 1 }, { N + 1}>> { loop {} }

we now get a mismatch const error of the following form:

error[E0308]: mismatched types
--> $DIR/mismatched-const-errors.rs:15:30
|
LL | fn foo2<const N: usize>() -> HasTrait<HasCastInTraitImpl<{ N + 1}, { N + 1 }>> {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `{ N + 1 }`, found `{ N + 1 + 1 }`
|
= note: expected type `{ N + 1 }`
found type `{ N + 1 + 1 }`

instead of the found { M + 1 } constant that was previously output.

[rust-highfive]

r? @jackh726

(rust-highfive has picked a reviewer for you, use r? to override)

[b-naber]

r? @BoxyUwU

[BoxyUwU]

I think this needs updating to print out with substs applied too

[b-naber]

Don't see why CI fails, I did bless those tests.

[BoxyUwU]

Can you check if this handles precedence right 🤔
if we have a const mismatch of like 3 * 2 + N and 3 * M where M is 2 + N i.e.

fnfoo<constM:usize>() -> [();3*M];let _:[();3*2 + N]foo::<{2 + N}>();

do we get a silly error message like expected `3 * 2 + N` found `3 * 2 + N`

[b-naber]

yeah we do, but I think it shouldn't be too hard to include precedence of operations here when constructing the suggestion. I can try that.

[bors]

☔ The latest upstream changes (presumably #91104) made this pull request unmergeable. Please resolve the merge conflicts.

[b-naber]

Taking precedence into account when applying substitutions is anything but straightforward. I'd prefer to do this in another PR, since this is basically more effort than the original PR.

For now I'd suggest we just fall back to the unsubstituted suggestion, in case we would output the same suggestion as the error.

[b-naber]

@BoxyUwU Would that be ok for you?

[b-naber]

Did decide to implement this, wasn't as hard as I initially thought.

[b-naber]

Ok, I only blessed the tests in ui/const-generics, but they all passed in that CI run. So it seems as if for some reason the try_create_suggestion_for_mismatched_const call returns None in CI, but Some(suggestion) locally on my machine. I'm completely flabbergasted as to why that might be. Is const-generics somehow platform dependent?

[bors]

☔ The latest upstream changes (presumably #91996) made this pull request unmergeable. Please resolve the merge conflicts.

[BoxyUwU]

This is the cause of the CI failures. the CI is failing on 32 bit stuff which means if we have a usize scalar here and call .to_i64 we get an InterpErrorInfo(InterpErrorInfoInner { kind: scalar size mismatch: expected 8 bytes but got 4 bytes instead, backtrace: None }) from this call but on 64bit it works fine because the sizes match.

the docs for to_i64 say "Fails if the scalar is a pointer" but I guess that is wrong .-.
this code would also just be wrong if the scalar was a u128 or something since those values cant all fit in a i128

not sure exactly what the right thing to replace this with is but we surely have code somewhere for printing this out

[b-naber]

Thanks, that's a great catch. I'll try to figure out how to handle this correctly here.

[b-naber]

For some reason I had to add the Cargo.lock file during the rebase (otherwise it wouldn't allow the rebase to continue). This seems to cause problems with CI now. What am I supposed to do here?

[rust-log-analyzer]

The job x86_64-gnu-llvm-12 failed! Check out the build log: (web)(plain)

Click to see the possible cause of the failure (guessed by this bot)

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---
---- [ui] ui/const-generics/defaults/generic-expr-default.rs stdout ----
diff of stderr:
4 LL | pub fn needs_evaluatable_bound<const N1: usize>() -> Foo<N1> {
6 |
6 |
- = help: try adding a `where` bound using this expression: `where [(); { N1 + 1 }]:`
Some tests failed in compiletest suite=ui mode=ui host=x86_64-unknown-linux-gnu target=i686-unknown-linux-gnu
+ = help: try adding a `where` bound using this expression: `where [(); { N + 1 }]:`
9 error: unconstrained generic constant
10 --> $DIR/generic-expr-default.rs:14:58
The actual stderr differed from the expected stderr.
Actual stderr saved to /checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/const-generics/defaults/generic-expr-default/generic-expr-default.stderr
To update references, rerun the tests and pass the `--bless` flag
To only update this specific test, also pass `--test-args const-generics/defaults/generic-expr-default.rs`
error: 1 errors occurred comparing output.
status: exit status: 1
command: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/bin/rustc" "/checkout/src/test/ui/const-generics/defaults/generic-expr-default.rs" "-Zthreads=1" "--target=i686-unknown-linux-gnu" "--error-format" "json" "--json" "future-incompat" "-Ccodegen-units=1" "-Zui-testing" "-Zdeduplicate-diagnostics=no" "--emit" "metadata" "-C" "prefer-dynamic" "--out-dir" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/const-generics/defaults/generic-expr-default" "-A" "unused" "-Crpath" "-O" "-Cdebuginfo=0" "-Lnative=/checkout/obj/build/i686-unknown-linux-gnu/native/rust-test-helpers" "-Clinker=cc" "-L" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/const-generics/defaults/generic-expr-default/auxiliary"
------------------------------------------
------------------------------------------
stderr:
stderr:
------------------------------------------
error: unconstrained generic constant
--> /checkout/src/test/ui/const-generics/defaults/generic-expr-default.rs:5:54
|
LL | pub fn needs_evaluatable_bound<const N1: usize>() -> Foo<N1> {
|
|
= help: try adding a `where` bound using this expression: `where [(); { N + 1 }]:`
error: unconstrained generic constant
--> /checkout/src/test/ui/const-generics/defaults/generic-expr-default.rs:14:58
|
|
LL | fn needs_evaluatable_bound_alias<T, const N: usize>() -> FooAlias<N>
|
|
= help: try adding a `where` bound using this expression: `where [(); { N + 1 }]:`
error: aborting due to 2 previous errors
------------------------------------------
------------------------------------------
---- [ui] ui/const-generics/generic_const_exprs/array-size-in-generic-struct-param.rs#full stdout ----
diff of stderr:
4 LL | struct ArithArrayLen<const N: usize>([u32; 0 + N]);
6 |
6 |
- = help: try adding a `where` bound using this expression: `where [(); { 0 + N }]:`
+ = help: try adding a `where` bound using this expression: `where [(); 0 + N]:`
9 error: overly complex generic constant
10 --> $DIR/array-size-in-generic-struct-param.rs:19:15
The actual stderr differed from the expected stderr.
Actual stderr saved to /checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/const-generics/generic_const_exprs/array-size-in-generic-struct-param.full/array-size-in-generic-struct-param.full.stderr
To only update this specific test, also pass `--test-args const-generics/generic_const_exprs/array-size-in-generic-struct-param.rs`
error in revision `full`: 1 errors occurred comparing output.
status: exit status: 1
command: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/bin/rustc" "/checkout/src/test/ui/const-generics/generic_const_exprs/array-size-in-generic-struct-param.rs" "-Zthreads=1" "--target=i686-unknown-linux-gnu" "--cfg" "full" "--error-format" "json" "--json" "future-incompat" "-Ccodegen-units=1" "-Zui-testing" "-Zdeduplicate-diagnostics=no" "--emit" "metadata" "-C" "prefer-dynamic" "--out-dir" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/const-generics/generic_const_exprs/array-size-in-generic-struct-param.full" "-A" "unused" "-Crpath" "-O" "-Cdebuginfo=0" "-Lnative=/checkout/obj/build/i686-unknown-linux-gnu/native/rust-test-helpers" "-Clinker=cc" "-L" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/const-generics/generic_const_exprs/array-size-in-generic-struct-param.full/auxiliary"
------------------------------------------
------------------------------------------
stderr:
stderr:
------------------------------------------
error: unconstrained generic constant
--> /checkout/src/test/ui/const-generics/generic_const_exprs/array-size-in-generic-struct-param.rs:8:38
|
LL | struct ArithArrayLen<const N: usize>([u32; 0 + N]);
|
|
= help: try adding a `where` bound using this expression: `where [(); 0 + N]:`
error: overly complex generic constant
--> /checkout/src/test/ui/const-generics/generic_const_exprs/array-size-in-generic-struct-param.rs:19:15
|
|
LL | arr: [u8; CFG.arr_size],
| ^^^^^^^^^^^^ field access is not supported in generic constant
|
= help: consider moving this anonymous constant into a `const` function
error: aborting due to 2 previous errors
------------------------------------------
---- [ui] ui/const-generics/mismatched-const-errors.rs stdout ----
diff of stderr:
4 LL | fn foo1<const N: usize>() -> HasTrait<HasCastInTraitImpl<{ N + 2}, { N }>> {
6 |
6 |
- = help: try adding a `where` bound using this expression: `where [(); { N + 2 + 1 }]:`
+ = help: try adding a `where` bound using this expression: `where [(); { M + 1 }]:`
8 note: required because of the requirements on the impl of `Trait` for `HasCastInTraitImpl<{ N + 2}, N>`
10 |
20 --> $DIR/mismatched-const-errors.rs:9:30
21 |
21 |
22 LL | fn foo1<const N: usize>() -> HasTrait<HasCastInTraitImpl<{ N + 2}, { N }>> {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `N`, found `{ N + 2 + 1 }`
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `N`, found `{ M + 1 }`
25 = note: expected type `N`
25 = note: expected type `N`
- found type `{ N + 2 + 1 }`
+ found type `{ M + 1 }`
28 error: unconstrained generic constant
29 --> $DIR/mismatched-const-errors.rs:15:30
31 LL | fn foo2<const N: usize>() -> HasTrait<HasCastInTraitImpl<{ N + 1}, { N + 1 }>> {
33 |
33 |
- = help: try adding a `where` bound using this expression: `where [(); { N + 1 + 1 }]:`
+ = help: try adding a `where` bound using this expression: `where [(); { M + 1 }]:`
35 note: required because of the requirements on the impl of `Trait` for `HasCastInTraitImpl<{ N + 1}, { N + 1 }>`
37 |
47 --> $DIR/mismatched-const-errors.rs:15:30
48 |
48 |
49 LL | fn foo2<const N: usize>() -> HasTrait<HasCastInTraitImpl<{ N + 1}, { N + 1 }>> {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `{ N + 1 }`, found `{ N + 1 + 1 }`
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `{ N + 1 }`, found `{ M + 1 }`
51 |
52 = note: expected type `{ N + 1 }`
- found type `{ N + 1 + 1 }`
+ found type `{ M + 1 }`
55 error: unconstrained generic constant
56 --> $DIR/mismatched-const-errors.rs:21:30
58 LL | fn foo3<const N: usize>() -> HasTrait<HasCastInTraitImpl<{ N + 1}, { N - 1}>> {
60 |
60 |
- = help: try adding a `where` bound using this expression: `where [(); { N + 1 + 1 }]:`
+ = help: try adding a `where` bound using this expression: `where [(); { M + 1 }]:`
62 note: required because of the requirements on the impl of `Trait` for `HasCastInTraitImpl<{ N + 1}, { N - 1}>`
64 |
74 --> $DIR/mismatched-const-errors.rs:21:30
75 |
75 |
76 LL | fn foo3<const N: usize>() -> HasTrait<HasCastInTraitImpl<{ N + 1}, { N - 1}>> {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `{ N - 1}`, found `{ N + 1 + 1 }`
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `{ N - 1}`, found `{ M + 1 }`
78 |
79 = note: expected type `{ N - 1}`
- found type `{ N + 1 + 1 }`
+ found type `{ M + 1 }`
82 error: unconstrained generic constant
83 --> $DIR/mismatched-const-errors.rs:27:44
85 LL | fn foo4<const N: usize>(c : [usize; N]) -> HasTrait<HasCastInTraitImpl<{ N - 1}, { N }>> {
87 |
87 |
- = help: try adding a `where` bound using this expression: `where [(); { N - 1 + 1 }]:`
+ = help: try adding a `where` bound using this expression: `where [(); { M + 1 }]:`
89 note: required because of the requirements on the impl of `Trait` for `HasCastInTraitImpl<{ N - 1}, N>`
91 |
101 --> $DIR/mismatched-const-errors.rs:27:44
102 |
102 |
103 LL | fn foo4<const N: usize>(c : [usize; N]) -> HasTrait<HasCastInTraitImpl<{ N - 1}, { N }>> {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `N`, found `{ N - 1 + 1 }`
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `N`, found `{ M + 1 }`
106 = note: expected type `N`
106 = note: expected type `N`
- found type `{ N - 1 + 1 }`
+ found type `{ M + 1 }`
109 error: unconstrained generic constant
110 --> $DIR/mismatched-const-errors.rs:33:30
112 LL | fn foo5<const N: usize>() -> HasTrait<HasCastInTraitImpl<{ N + N }, { 2 * N }>> {
114 |
114 |
- = help: try adding a `where` bound using this expression: `where [(); { N + N + 1 }]:`
+ = help: try adding a `where` bound using this expression: `where [(); { M + 1 }]:`
116 note: required because of the requirements on the impl of `Trait` for `HasCastInTraitImpl<{ N + N }, { 2 * N }>`
118 |
128 --> $DIR/mismatched-const-errors.rs:33:30
129 |
129 |
130 LL | fn foo5<const N: usize>() -> HasTrait<HasCastInTraitImpl<{ N + N }, { 2 * N }>> {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `{ 2 * N }`, found `{ N + N + 1 }`
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `{ 2 * N }`, found `{ M + 1 }`
132 |
133 = note: expected type `{ 2 * N }`
- found type `{ N + N + 1 }`
+ found type `{ M + 1 }`
136 error: aborting due to 10 previous errors
137 The actual stderr differed from the expected stderr.
Actual stderr saved to /checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/const-generics/mismatched-const-errors/mismatched-const-errors.stderr
To update references, rerun the tests and pass the `--bless` flag
To only update this specific test, also pass `--test-args const-generics/mismatched-const-errors.rs`
error: 1 errors occurred comparing output.
status: exit status: 1
command: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/bin/rustc" "/checkout/src/test/ui/const-generics/mismatched-const-errors.rs" "-Zthreads=1" "--target=i686-unknown-linux-gnu" "--error-format" "json" "--json" "future-incompat" "-Ccodegen-units=1" "-Zui-testing" "-Zdeduplicate-diagnostics=no" "--emit" "metadata" "-C" "prefer-dynamic" "--out-dir" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/const-generics/mismatched-const-errors" "-A" "unused" "-Crpath" "-O" "-Cdebuginfo=0" "-Lnative=/checkout/obj/build/i686-unknown-linux-gnu/native/rust-test-helpers" "-Clinker=cc" "-L" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/const-generics/mismatched-const-errors/auxiliary"
------------------------------------------
------------------------------------------
stderr:
stderr:
------------------------------------------
error: unconstrained generic constant
--> /checkout/src/test/ui/const-generics/mismatched-const-errors.rs:9:30
|
LL | fn foo1<const N: usize>() -> HasTrait<HasCastInTraitImpl<{ N + 2}, { N }>> {
|
|
= help: try adding a `where` bound using this expression: `where [(); { M + 1 }]:`
note: required because of the requirements on the impl of `Trait` for `HasCastInTraitImpl<{ N + 2}, N>`
|
|
LL | impl<const M: usize> Trait for HasCastInTraitImpl<M, { M + 1 }> {}
| ^^^^^ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: required by a bound in `HasTrait`
|
|
LL | pub struct HasTrait<T: Trait>(T);
| ^^^^^ required by this bound in `HasTrait`
error[E0308]: mismatched types
--> /checkout/src/test/ui/const-generics/mismatched-const-errors.rs:9:30
|
|
LL | fn foo1<const N: usize>() -> HasTrait<HasCastInTraitImpl<{ N + 2}, { N }>> {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `N`, found `{ M + 1 }`
= note: expected type `N`
= note: expected type `N`
found type `{ M + 1 }`
error: unconstrained generic constant
--> /checkout/src/test/ui/const-generics/mismatched-const-errors.rs:15:30
|
|
LL | fn foo2<const N: usize>() -> HasTrait<HasCastInTraitImpl<{ N + 1}, { N + 1 }>> {
|
|
= help: try adding a `where` bound using this expression: `where [(); { M + 1 }]:`
note: required because of the requirements on the impl of `Trait` for `HasCastInTraitImpl<{ N + 1}, { N + 1 }>`
|
|
LL | impl<const M: usize> Trait for HasCastInTraitImpl<M, { M + 1 }> {}
| ^^^^^ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: required by a bound in `HasTrait`
|
|
LL | pub struct HasTrait<T: Trait>(T);
| ^^^^^ required by this bound in `HasTrait`
error[E0308]: mismatched types
--> /checkout/src/test/ui/const-generics/mismatched-const-errors.rs:15:30
|
|
LL | fn foo2<const N: usize>() -> HasTrait<HasCastInTraitImpl<{ N + 1}, { N + 1 }>> {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `{ N + 1 }`, found `{ M + 1 }`
|
= note: expected type `{ N + 1 }`
found type `{ M + 1 }`
error: unconstrained generic constant
--> /checkout/src/test/ui/const-generics/mismatched-const-errors.rs:21:30
|
|
LL | fn foo3<const N: usize>() -> HasTrait<HasCastInTraitImpl<{ N + 1}, { N - 1}>> {
|
|
= help: try adding a `where` bound using this expression: `where [(); { M + 1 }]:`
note: required because of the requirements on the impl of `Trait` for `HasCastInTraitImpl<{ N + 1}, { N - 1}>`
|
|
LL | impl<const M: usize> Trait for HasCastInTraitImpl<M, { M + 1 }> {}
| ^^^^^ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: required by a bound in `HasTrait`
|
|
LL | pub struct HasTrait<T: Trait>(T);
| ^^^^^ required by this bound in `HasTrait`
error[E0308]: mismatched types
--> /checkout/src/test/ui/const-generics/mismatched-const-errors.rs:21:30
|
|
LL | fn foo3<const N: usize>() -> HasTrait<HasCastInTraitImpl<{ N + 1}, { N - 1}>> {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `{ N - 1}`, found `{ M + 1 }`
|
= note: expected type `{ N - 1}`
found type `{ M + 1 }`
error: unconstrained generic constant
--> /checkout/src/test/ui/const-generics/mismatched-const-errors.rs:27:44
|
|
LL | fn foo4<const N: usize>(c : [usize; N]) -> HasTrait<HasCastInTraitImpl<{ N - 1}, { N }>> {
|
|
= help: try adding a `where` bound using this expression: `where [(); { M + 1 }]:`
note: required because of the requirements on the impl of `Trait` for `HasCastInTraitImpl<{ N - 1}, N>`
|
|
LL | impl<const M: usize> Trait for HasCastInTraitImpl<M, { M + 1 }> {}
| ^^^^^ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: required by a bound in `HasTrait`
|
|
LL | pub struct HasTrait<T: Trait>(T);
| ^^^^^ required by this bound in `HasTrait`
error[E0308]: mismatched types
--> /checkout/src/test/ui/const-generics/mismatched-const-errors.rs:27:44
|
|
LL | fn foo4<const N: usize>(c : [usize; N]) -> HasTrait<HasCastInTraitImpl<{ N - 1}, { N }>> {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `N`, found `{ M + 1 }`
= note: expected type `N`
= note: expected type `N`
found type `{ M + 1 }`
error: unconstrained generic constant
--> /checkout/src/test/ui/const-generics/mismatched-const-errors.rs:33:30
|
|
LL | fn foo5<const N: usize>() -> HasTrait<HasCastInTraitImpl<{ N + N }, { 2 * N }>> {
|
|
= help: try adding a `where` bound using this expression: `where [(); { M + 1 }]:`
note: required because of the requirements on the impl of `Trait` for `HasCastInTraitImpl<{ N + N }, { 2 * N }>`
|
|
LL | impl<const M: usize> Trait for HasCastInTraitImpl<M, { M + 1 }> {}
| ^^^^^ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: required by a bound in `HasTrait`
|
|
LL | pub struct HasTrait<T: Trait>(T);
| ^^^^^ required by this bound in `HasTrait`
error[E0308]: mismatched types
--> /checkout/src/test/ui/const-generics/mismatched-const-errors.rs:33:30
|
|
LL | fn foo5<const N: usize>() -> HasTrait<HasCastInTraitImpl<{ N + N }, { 2 * N }>> {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `{ 2 * N }`, found `{ M + 1 }`
|
= note: expected type `{ 2 * N }`
found type `{ M + 1 }`
error: aborting due to 10 previous errors
For more information about this error, try `rustc --explain E0308`.
------------------------------------------
---- [ui] ui/const-generics/mismatched-const-types-precedence.rs stdout ----
diff of stderr:
4 LL | let _: [u32; 3 * 2 + N + K] = foo::<{ 2 + N }, K>(a, b);
6 |
6 |
- = help: try adding a `where` bound using this expression: `where [(); { 3 * { 2 + N + K } }]:`
+ = help: try adding a `where` bound using this expression: `where [(); 3 * {M + K}]:`
8 note: required by a bound in `foo`
10 |
17 LL | let _: [u32; 3 * 2 + N + K] = foo::<{ 2 + N }, K>(a, b);
19 |
19 |
- = help: try adding a `where` bound using this expression: `where [(); { 3 * 2 + N + K }]:`
+ = help: try adding a `where` bound using this expression: `where [(); 3 * 2 + N + K]:`
22 error[E0308]: mismatched types
23 --> $DIR/mismatched-const-types-precedence.rs:6:33
24 |
24 |
25 LL | let _: [u32; 3 * 2 + N + K] = foo::<{ 2 + N }, K>(a, b);
- | ^^^^^^^^^^^^^^^^^^^^^^^^^ expected `3 * 2 + N + K`, found `{ 3 * { 2 + N + K } }`
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^ expected `3 * 2 + N + K`, found `3 * {M + K}`
27 |
28 = note: expected type `3 * 2 + N + K`
- found type `{ 3 * { 2 + N + K } }`
+ found type `3 * {M + K}`
31 error: unconstrained generic constant
32 --> $DIR/mismatched-const-types-precedence.rs:6:33
34 LL | let _: [u32; 3 * 2 + N + K] = foo::<{ 2 + N }, K>(a, b);
36 |
36 |
- = help: try adding a `where` bound using this expression: `where [(); { 3 * { 2 + N + K } }]:`
+ = help: try adding a `where` bound using this expression: `where [(); 3 * {M + K}]:`
38 note: required by a bound in `foo`
40 |
55 LL | let _: [u32; 3 * 2 + N * K] = foo2::<{ 2 + N }, K>(a, b);
57 |
57 |
- = help: try adding a `where` bound using this expression: `where [(); { 3 * { 2 + N } * K }]:`
+ = help: try adding a `where` bound using this expression: `where [(); 3 * M * K]:`
59 note: required by a bound in `foo2`
61 |
68 LL | let _: [u32; 3 * 2 + N * K] = foo2::<{ 2 + N }, K>(a, b);
70 |
70 |
- = help: try adding a `where` bound using this expression: `where [(); { 3 * 2 + N * K }]:`
+ = help: try adding a `where` bound using this expression: `where [(); 3 * 2 + N * K]:`
73 error[E0308]: mismatched types
74 --> $DIR/mismatched-const-types-precedence.rs:18:33
75 |
75 |
76 LL | let _: [u32; 3 * 2 + N * K] = foo2::<{ 2 + N }, K>(a, b);
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `3 * 2 + N * K`, found `{ 3 * { 2 + N } * K }`
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `3 * 2 + N * K`, found `3 * M * K`
78 |
79 = note: expected type `3 * 2 + N * K`
- found type `{ 3 * { 2 + N } * K }`
+ found type `3 * M * K`
82 error: unconstrained generic constant
83 --> $DIR/mismatched-const-types-precedence.rs:18:33
85 LL | let _: [u32; 3 * 2 + N * K] = foo2::<{ 2 + N }, K>(a, b);
87 |
87 |
- = help: try adding a `where` bound using this expression: `where [(); { 3 * { 2 + N } * K }]:`
+ = help: try adding a `where` bound using this expression: `where [(); 3 * M * K]:`
89 note: required by a bound in `foo2`
91 |
106 LL | let _: [u32; 3 * 2 + N * K + L] = foo3::<{ 2 + N }, K, L>(a, b);
108 |
108 |
- = help: try adding a `where` bound using this expression: `where [(); { 3 * { 2 + N } * K + L }]:`
+ = help: try adding a `where` bound using this expression: `where [(); 3 * M * {K + L}]:`
110 note: required by a bound in `foo3`
112 |
121 LL | let _: [u32; 3 * 2 + N * K + L] = foo3::<{ 2 + N }, K, L>(a, b);
123 |
123 |
- = help: try adding a `where` bound using this expression: `where [(); { 3 * 2 + N * K + L }]:`
+ = help: try adding a `where` bound using this expression: `where [(); 3 * 2 + N * K + L]:`
126 error[E0308]: mismatched types
127 --> $DIR/mismatched-const-types-precedence.rs:30:37
128 |
128 |
129 LL | let _: [u32; 3 * 2 + N * K + L] = foo3::<{ 2 + N }, K, L>(a, b);
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `3 * 2 + N * K + L`, found `{ 3 * { 2 + N } * K + L }`
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `3 * 2 + N * K + L`, found `3 * M * {K + L}`
131 |
132 = note: expected type `3 * 2 + N * K + L`
- found type `{ 3 * { 2 + N } * K + L }`
+ found type `3 * M * {K + L}`
135 error: unconstrained generic constant
136 --> $DIR/mismatched-const-types-precedence.rs:30:37
138 LL | let _: [u32; 3 * 2 + N * K + L] = foo3::<{ 2 + N }, K, L>(a, b);
140 |
140 |
- = help: try adding a `where` bound using this expression: `where [(); { 3 * { 2 + N } * K + L }]:`
+ = help: try adding a `where` bound using this expression: `where [(); 3 * M * {K + L}]:`
142 note: required by a bound in `foo3`
144 |
The actual stderr differed from the expected stderr.
The actual stderr differed from the expected stderr.
Actual stderr saved to /checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/const-generics/mismatched-const-types-precedence/mismatched-const-types-precedence.stderr
To update references, rerun the tests and pass the `--bless` flag
To only update this specific test, also pass `--test-args const-generics/mismatched-const-types-precedence.rs`
error: 1 errors occurred comparing output.
status: exit status: 1
command: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/bin/rustc" "/checkout/src/test/ui/const-generics/mismatched-const-types-precedence.rs" "-Zthreads=1" "--target=i686-unknown-linux-gnu" "--error-format" "json" "--json" "future-incompat" "-Ccodegen-units=1" "-Zui-testing" "-Zdeduplicate-diagnostics=no" "--emit" "metadata" "-C" "prefer-dynamic" "--out-dir" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/const-generics/mismatched-const-types-precedence" "-A" "unused" "-Crpath" "-O" "-Cdebuginfo=0" "-Lnative=/checkout/obj/build/i686-unknown-linux-gnu/native/rust-test-helpers" "-Clinker=cc" "-L" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/const-generics/mismatched-const-types-precedence/auxiliary"
---
test result: FAILED. 12345 passed; 4 failed; 173 ignored; 0 measured; 0 filtered out; finished in 106.82s
command did not execute successfully: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage0-tools-bin/compiletest" "--compile-lib-path" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/lib" "--run-lib-path" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/lib/rustlib/i686-unknown-linux-gnu/lib" "--rustc-path" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/bin/rustc" "--src-base" "/checkout/src/test/ui" "--build-base" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui" "--stage-id" "stage2-i686-unknown-linux-gnu" "--suite" "ui" "--mode" "ui" "--target" "i686-unknown-linux-gnu" "--host" "x86_64-unknown-linux-gnu" "--llvm-filecheck" "/usr/lib/llvm-12/bin/FileCheck" "--pass" "check" "--nodejs" "/usr/bin/node" "--linker" "cc" "--host-rustcflags" "-Crpath -O -Cdebuginfo=0 -Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers" "--target-rustcflags" "-Crpath -O -Cdebuginfo=0 -Lnative=/checkout/obj/build/i686-unknown-linux-gnu/native/rust-test-helpers" "--docck-python" "/usr/bin/python3" "--lldb-python" "/usr/bin/python3" "--gdb" "/usr/bin/gdb" "--quiet" "--llvm-version" "12.0.0" "--llvm-components" "aarch64 aarch64asmparser aarch64codegen aarch64desc aarch64disassembler aarch64info aarch64utils aggressiveinstcombine all all-targets amdgpu amdgpuasmparser amdgpucodegen amdgpudesc amdgpudisassembler amdgpuinfo amdgpuutils analysis arm armasmparser armcodegen armdesc armdisassembler arminfo armutils asmparser asmprinter avr avrasmparser avrcodegen avrdesc avrdisassembler avrinfo binaryformat bitreader bitstreamreader bitwriter bpf bpfasmparser bpfcodegen bpfdesc bpfdisassembler bpfinfo cfguard codegen core coroutines coverage debuginfocodeview debuginfodwarf debuginfogsym debuginfomsf debuginfopdb demangle dlltooldriver dwarflinker engine executionengine extensions filecheck frontendopenacc frontendopenmp fuzzmutate globalisel hellonew hexagon hexagonasmparser hexagoncodegen hexagondesc hexagondisassembler hexagoninfo instcombine instrumentation interfacestub interpreter ipo irreader jitlink lanai lanaiasmparser lanaicodegen lanaidesc lanaidisassembler lanaiinfo libdriver lineeditor linker lto mc mca mcdisassembler mcjit mcparser mips mipsasmparser mipscodegen mipsdesc mipsdisassembler mipsinfo mirparser msp430 msp430asmparser msp430codegen msp430desc msp430disassembler msp430info native nativecodegen nvptx nvptxcodegen nvptxdesc nvptxinfo objcarcopts object objectyaml option orcjit orcshared orctargetprocess passes perfjitevents powerpc powerpcasmparser powerpccodegen powerpcdesc powerpcdisassembler powerpcinfo profiledata remarks riscv riscvasmparser riscvcodegen riscvdesc riscvdisassembler riscvinfo runtimedyld scalaropts selectiondag sparc sparcasmparser sparccodegen sparcdesc sparcdisassembler sparcinfo support symbolize systemz systemzasmparser systemzcodegen systemzdesc systemzdisassembler systemzinfo tablegen target textapi transformutils vectorize webassembly webassemblyasmparser webassemblycodegen webassemblydesc webassemblydisassembler webassemblyinfo windowsmanifest x86 x86asmparser x86codegen x86desc x86disassembler x86info xcore xcorecodegen xcoredesc xcoredisassembler xcoreinfo xray" "--cc" "" "--cxx" "" "--cflags" "" "--adb-path" "adb" "--adb-test-dir" "/data/tmp/work" "--android-cross-path" "" "--channel" "nightly" "--color" "always"
Build completed unsuccessfully in 0:01:49

[bors]

☔ The latest upstream changes (presumably #92556) made this pull request unmergeable. Please resolve the merge conflicts.

[JohnCSimon]

Ping from triage:
@b-naber can you post your status on this PR? It has sat idle for almost a month.

[b-naber]

@BoxyUwU Any ideas why try_to_string doesn't work in light of what you said about the origin of the CI failures? I also find it weird that CI passed prior to the 'implement precedence for anon const mismatch' commit even though `to_i64' was used in the 'allow AbstractConsts to be printed' commit already (Actually it looks as if CI never passed). And there isn't any other existing function to print Scalars in non-hex representation.

[BoxyUwU]

Not sure why your code isnt working but I looked around a bit and I think PrettyPrinter::pretty_print_const_scalar can be used to get it printed properly.

[JohnCSimon]

@b-naber
Ping from triage: I'm closing this due to inactivity, Please reopen when you are ready to continue with this. Thanks for your contribution.

@rustbot label: +S-inactive