Add signed num::NonZeroI* types #57475

SimonSapin · 2019-01-09T18:48:38Z

Multiple people have asked for them in #49137. Given that the unsigned ones already exist, they are very easy to add and not an additional maintenance burden.

rust-highfive · 2019-01-09T18:48:43Z

r? @aidanhs

(rust_highfive has picked a reviewer for you, use r? to override)

SimonSapin · 2019-01-09T18:54:00Z

The new types are stable in this PR, so let’s get team sign-off:

@rfcbot fcp merge

They don’t really need to be. But they are very similar to the existing unsigned non-zero integer types, so it seems to me that having them as unstable for a period of time is very unlikely to bring new information. Also, making the signed and unsigned type behave differently (beyond signedness) or have different API seems like it would be unfortunate, and the latter are already stable.

rfcbot · 2019-01-09T18:54:01Z

Team member @SimonSapin has proposed to merge this. The next step is review by the rest of the tagged teams:

No concerns currently listed.

Once a majority of reviewers approve (and none object), this will enter its final comment period. If you spot a major issue that hasn't been raised at any point in this process, please speak up!

See this document for info about what commands tagged team members can give me.

rust-highfive · 2019-01-09T19:57:51Z

The job x86_64-gnu-llvm-6.0 of your PR failed on Travis (raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.

travis_time:end:1ab20504:start=1547059796556912748,finish=1547059797474349550,duration=917436802
$ git checkout -qf FETCH_HEAD
travis_fold:end:git.checkout

Encrypted environment variables have been removed for security reasons.
See https://docs.travis-ci.com/user/pull-requests/#pull-requests-and-security-restrictions
$ export SCCACHE_BUCKET=rust-lang-ci-sccache2
$ export SCCACHE_REGION=us-west-1
Setting environment variables from .travis.yml
$ export IMAGE=x86_64-gnu-llvm-6.0
---
[00:04:38] 71  |                           Some(unsafe { $Ty(n) })
[00:04:38]     |                                ^^^^^^ unnecessary `unsafe` block
[00:04:38] ...
[00:04:38] 100 | / nonzero_integers! {
[00:04:38] 101 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU8(u8);
[00:04:38] 102 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU16(u16);
[00:04:38] 103 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU32(u32);
[00:04:38] ...   |
[00:04:38] 112 | |     #[stable(feature = "signed_nonzero", since = "1.33.0")] NonZeroIsize(isize);
[00:04:38]     | |_- in this macro invocation
[00:04:38]     |
[00:04:38]     = note: #[warn(unused_unsafe)] on by default
[00:04:38] 
[00:04:38] 
[00:04:38] warning: unnecessary `unsafe` block
[00:04:38]    --> src/libcore/num/mod.rs:71:30
[00:04:38]     |
[00:04:38] 71  |                           Some(unsafe { $Ty(n) })
[00:04:38]     |                                ^^^^^^ unnecessary `unsafe` block
[00:04:38] ...
[00:04:38] 100 | / nonzero_integers! {
[00:04:38] 101 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU8(u8);
[00:04:38] 102 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU16(u16);
[00:04:38] 103 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU32(u32);
[00:04:38] ...   |
[00:04:38] 112 | |     #[stable(feature = "signed_nonzero", since = "1.33.0")] NonZeroIsize(isize);
[00:04:38]     | |_- in this macro invocation
[00:04:38] 
[00:04:38] warning: unnecessary `unsafe` block
[00:04:38]     --> src/libcore/ptr.rs:2785:18
---
[00:04:38] 50  |                   #[rustc_layout_scalar_valid_range_start(1)]
[00:04:38]     |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[00:04:38] ...
[00:04:38] 100 | / nonzero_integers! {
[00:04:38] 101 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU8(u8);
[00:04:38] 102 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU16(u16);
[00:04:38] 103 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU32(u32);
[00:04:38] ...   |
[00:04:38] 112 | |     #[stable(feature = "signed_nonzero", since = "1.33.0")] NonZeroIsize(isize);
[00:04:38]     | |_- in this macro invocation
[00:04:38]     |
[00:04:38]     = note: #[warn(unused_attributes)] on by default
[00:04:38] 
[00:04:38] 
[00:04:38] warning: unused attribute
[00:04:38]    --> src/libcore/num/mod.rs:50:17
[00:04:38]     |
[00:04:38] 50  |                   #[rustc_layout_scalar_valid_range_start(1)]
[00:04:38]     |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[00:04:38] ...
[00:04:38] 100 | / nonzero_integers! {
[00:04:38] 101 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU8(u8);
[00:04:38] 102 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU16(u16);
[00:04:38] 103 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU32(u32);
[00:04:38] ...   |
[00:04:38] 112 | |     #[stable(feature = "signed_nonzero", since = "1.33.0")] NonZeroIsize(isize);
[00:04:38]     | |_- in this macro invocation
[00:04:38] 
[00:04:38] warning: unused attribute
[00:04:38]     --> src/libcore/ptr.rs:2720:1
---
[01:07:11] .................................................................................................... 4600/5298
[01:07:15] .................................................................................................... 4700/5298
[01:07:18] .................................................................................................... 4800/5298
[01:07:23] .................................................................................................... 4900/5298
[01:07:27] ..............................................F..................................................... 5000/5298
[01:07:33] .................................................................................................... 5200/5298
[01:07:36] .....................................i............................................................
[01:07:36] failures:
[01:07:36] 
[01:07:36] 
[01:07:36] ---- [ui] ui/try-block/try-block-bad-type.rs stdout ----
[01:07:36] diff of stderr:
[01:07:36] 
[01:07:36] 5    |         ^^^^^^^^ the trait `std::convert::From<&str>` is not implemented for `i32`
[01:07:36] 7    = help: the following implementations were found:
[01:07:36] 7    = help: the following implementations were found:
[01:07:36] -              <i32 as std::convert::From<bool>>
[01:07:36] +              <i32 as std::convert::From<core::num::NonZeroI32>>
[01:07:36] 9              <i32 as std::convert::From<i16>>
[01:07:36] 10              <i32 as std::convert::From<i8>>
[01:07:36] -              <i32 as std::convert::From<u16>>
[01:07:36] 12              <i32 as std::convert::From<u8>>
[01:07:36] 13    = note: required by `std::convert::From::from`
[01:07:36] 14 
[01:07:36] 14 
[01:07:36] 15 error[E0271]: type mismatch resolving `<std::result::Result<i32, i32> as std::ops::Try>::Ok == &str`
[01:07:36] 
[01:07:36] The actual stderr differed from the expected stderr.
[01:07:36] Actual stderr saved to /checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/try-block/try-block-bad-type/try-block-bad-type.stderr
[01:07:36] Actual stderr saved to /checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/try-block/try-block-bad-type/try-block-bad-type.stderr
[01:07:36] To update references, rerun the tests and pass the `--bless` flag
[01:07:36] To only update this specific test, also pass `--test-args try-block/try-block-bad-type.rs`
[01:07:36] error: 1 errors occurred comparing output.
[01:07:36] status: exit code: 1
[01:07:36] status: exit code: 1
[01:07:36] command: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/bin/rustc" "/checkout/src/test/ui/try-block/try-block-bad-type.rs" "--target=x86_64-unknown-linux-gnu" "--error-format" "json" "-Zui-testing" "-C" "prefer-dynamic" "-o" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/try-block/try-block-bad-type/a" "-Crpath" "-O" "-Zunstable-options" "-Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers" "--edition" "2018" "-L" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/try-block/try-block-bad-type/auxiliary" "-A" "unused"
[01:07:36] ------------------------------------------
[01:07:36] 
[01:07:36] ------------------------------------------
[01:07:36] stderr:
[01:07:36] stderr:
[01:07:36] ------------------------------------------
[01:07:36] {"message":"the trait bound `i32: std::convert::From<&str>` is not satisfied","code":{"code":"E0277","explanation":"\nYou tried to use a type which doesn't implement some trait in a place which\nexpected that trait. Erroneous code example:\n\n```compile_fail,E0277\n// here we declare the Foo trait with a bar method\ntrait Foo {\n    fn bar(&self);\n}\n\n// we now declare a function which takes an object implementing the Foo trait\nfn some_func<T: Foo>(foo: T) {\n    foo.bar();\n}\n\nfn main() {\n    // we now call the method with the i32 type, which doesn't implement\n    // the Foo trait\n    some_func(5i32); // error: the trait bound `i32 : Foo` is not satisfied\n}\n```\n\nIn order to fix this error, verify that the type you're using does implement\nthe trait. Example:\n\n```\ntrait Foo {\n    fn bar(&self);\n}\n\nfn some_func<T: Foo>(foo: T) {\n    foo.bar(); // we can now use this method since i32 implements the\n               // Foo trait\n}\n\n// we implement the trait on the i32 type\nimpl Foo for i32 {\n    fn bar(&self) {}\n}\n\nfn main() {\n    some_func(5i32); // ok!\n}\n```\n\nOr in a generic context, an erroneous code example would look like:\n\n```compile_fail,E0277\nfn some_func<T>(foo: T) {\n    println!(\"{:?}\", foo); // error: the trait `core::fmt::Debug` is not\n                           //        implemented for the type `T`\n}\n\nfn main() {\n    // We now call the method with the i32 type,\n    // which *does* implement the Debug trait.\n    some_func(5i32);\n}\n```\n\nNote that the error here is in the definition of the generic function: Although\nwe only call it with a parameter that does implement `Debug`, the compiler\nstill rejects the function: It must work with all possible input types. In\norder to make this example compile, we need to restrict the generic type we're\naccepting:\n\n```\nuse std::fmt;\n\n// Restrict the input type to types that implement Debug.\nfn some_func<T: fmt::Debug>(foo: T) {\n    println!(\"{:?}\", foo);\n}\n\nfn main() {\n    // Calling the method is still fine, as i32 implements Debug.\n    some_func(5i32);\n\n    // This would fail to compile now:\n    // struct WithoutDebug;\n    // some_func(WithoutDebug);\n}\n```\n\nRust only looks at the signature of the called function, as such it must\nalready specify all requirements that will be used for every type parameter.\n"},"level":"error","spans":[{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":121,"byte_end":129,"line_start":7,"line_end":7,"column_start":9,"column_end":17,"is_primary":true,"text":[{"text":"        Err(\"\")?; //~ ERROR the trait bound `i32: std::convert::From<&str>` is not satisfied","highlight_start":9,"highlight_end":17}],"label":"the trait `std::convert::From<&str>` is not implemented for `i32`","suggested_replacement":null,"suggestion_applicability":null,"expansion":null}],"children":[{"message":"the following implementations were found:\n  <i32 as std::convert::From<core::num::NonZeroI32>>\n  <i32 as std::convert::From<i16>>\n  <i32 as std::convert::From<i8>>\n  <i32 as std::convert::From<u8>>\nand 2 others","code":null,"level":"help","spans":[],"children":[],"rendered":null},{"message":"required by `std::convert::From::from`","code":null,"level":"note","spans":[],"children":[],"rendered":null}],"rendered":"error[E0277]: the trait bound `i32: std::convert::From<&str>` is not satisfied\n  --> /checkout/src/test/ui/try-block/try-block-bad-type.rs:7:9\n   |\nLL |         Err(\"\")?; //~ ERROR the trait bound `i32: std::convert::From<&str>` is not satisfied\n   |         ^^^^^^^^ the trait `std::convert::From<&str>` is not implemented for `i32`\n   |\n   = help: the following implementations were found:\n             <i32 as std::convert::From<core::num::NonZeroI32>>\n             <i32 as std::convert::From<i16>>\n             <i32 as std::convert::From<i8>>\n             <i32 as std::convert::From<u8>>\n           and 2 others\n   = note: required by `std::convert::From::from`\n\n"}
[01:07:36] {"message":"type mismatch resolving `<std::result::Result<i32, i32> as std::ops::Try>::Ok == &str`","code":{"code":"E0271","explanation":"\nThis is because of a type mismatch between the associated type of some\ntrait (e.g., `T::Bar`, where `T` implements `trait Quux { type Bar; }`)\nand another type `U` that is required to be equal to `T::Bar`, but is not.\nExamples follow.\n\nHere is a basic example:\n\n```compile_fail,E0271\ntrait Trait { type AssociatedType; }\n\nfn foo<T>(t: T) where T: Trait<AssociatedType=u32> {\n    println!(\"in foo\");\n}\n\nimpl Trait for i8 { type AssociatedType = &'static str; }\n\nfoo(3_i8);\n```\n\nHere is that same example again, with some explanatory comments:\n\n```compile_fail,E0271\ntrait Trait { type AssociatedType; }\n\nfn foo<T_i8);\n\n// For-Loop Example:\nlet vs = vec![1, 2, 3, 4];\nfor v in &vs {\n    match v {\n        &1 => {}\n        _ => {}\n    }\n}\n```\n"},"level":"error","spans":[{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":270,"byte_end":272,"line_start":12,"line_end":12,"column_start":9,"column_end":11,"is_primary":true,"text":[{"text":"        \"\" //~ ERROR type mismatch","highlight_start":9,"highlight_end":11}],"label":"expected i32, found &str","suggested_replacement":null,"suggestion_applicability":null,"expansion":null}],"children":[{"message":"expected type `i32`\n   found type `&str`","code":null,"level":"note","spans":[],"children":[],"rendered":null}],"rendered":"error[E0271]: type mismatch resolving `<std::result::Result<i32, i32> as std::ops::Try>::Ok == &str`\n  --> /checkout/src/test/ui/try-block/try-block-bad-type.rs:12:9\n   |\nLL |         \"\" //~ ERROR type mismatch\n   |         ^^ expected i32, found &str\n   |\n   = note: expected type `i32`\n              found type `&str`\n\n"}
[01:07:36] {"message":"type mismatch resolving `<std::result::Result<i32, i32> as std::ops::Try>::Ok == ()`","code":{"code":"E0271","explanation":"\nThis is because of a type mismatch between the associated type of some\ntrait (e.g., `T::Bar`, where `T` implements `trait Quux { type Bar; }`)\nand another type `U` that is required to be equal to `T::Bar`, but is not.\nExamples follow.\n\nHere is a basic example:\n\n```compile_fail,E0271\ntrait Trait { type AssociatedType; }\n\nfn foo<T>(t: T) where T: Trait<AssociatedType=u32> {\n    println!(\"in foo\");\n}\n\nimpl Trait for i8 { type AssociatedType = &'static str; }\n\nfoo(3_i8);\n```\n\nHere is that same example again, with some explanatory comments:\n\n```compile_fail,E0271\ntrait Trait { type AssociatedType; }\n\nfn foo<T>(t: T) where T: Trait<AssociatedType=u32> {\n//                    ~~~~~~~~ ~~~~~~~~~~~~~~~~~~\n//                        |            |\n//         This says `foo` can         |\n//           only be used with         |\n//              some type that         |\n//         implements `Trait`.         |\n//                                     |\n//                             This says not only must\n//                             `T` be an impl of `Trait`\n//                             but also that the impl\n//                             must assign the type `u32`\n//                             to the associated type.\n    println!(\"in foo\");\n}\n\nimpl Trait for i8 { type AssociatedType = &'static str; }\n//~~~~~~~~~~~~~~~   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n//      |                             |\n// `i8` does have                     |\n// implementation                     |\n// of `Trait`...                      |\n//                     ... but it is an implementation\n//                     that assigns `&'static str` to\n//                     the associated type.\n\nfoo(3_i8);\n// Here, we invoke `foo` with an `i8`, which does not satisfy\n// the constraint `<i8 as Trait>::AssociatedType=u32`, and\n// therefore the type-checker complains with this error code.\n```\n\nTo avoid those issues, you have to make the types match correctly.\nSo we can fix the previous examples like this:\n\n```\n// Basic Example:\ntrait Trait { type AssociatedType; }\n\nfn foo<T>(t: T) where T: Trait<AssociatedType = &'static str> {\n    println!(\"in foo\");\n}\n\nimpl Trait for i8 { type AssociatedType = &'static str; }\n\nfoo(3_i8);\n\n// For-Loop Example:\nlet vs = vec![1, 2, 3, 4];\nfor v in &vs {\n    match v {\n        &1 => {}\n        _ => {}\n    }\n}\n```\n"},"level":"error","spans":[{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":343,"byte_end":344,"line_start":15,"line_end":15,"column_start":39,"column_end":40,"is_primary":true,"text":[{"text":"    let res: Result<i32, i32> = try { }; //~ ERROR type mismatch","highlight_start":39,"highlight_end":40}],"label":"expected i32, found ()","suggested_replacement":null,"suggestion_applicability":null,"expansion":{"span":{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":341,"byte_end":344,"line_start":15,"line_end":15,"column_start":37,"column_end":40,"is_primary":false,"text":[{"text":"    let res: Result<i32, i32> = try { }; //~ ERROR type mismatch","highlight_start":37,"highlight_end":40}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null},"macro_decl_name":"desugaring of `try block`","def_site_span":{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":341,"byte_end":344,"line_start":15,"line_end":15,"column_start":37,"column_end":40,"is_primary":false,"text":[{"text":"    let res: Result<i32, i32> = try { }; //~ ERROR type mismatch","highlight_start":37,"highlight_end":40}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null}}}],"children":[{"message":"expected type `i32`\n   found type `()`","code":null,"level":"note","spans":[],"children":[],"rendered":null}],"rendered":"error[E0271]: type mismatch resolving `<std::result::Result<i32, i32> as std::ops::Try>::Ok == ()`\n  --> /checkout/src/test/ui/try-block/try-block-bad-type.rs:15:39\n   |\nLL |     let res: Result<i32, i32> = try { }; //~ ERROR type mismatch\n   |                                       ^ expected i32, found ()\n   |\n   = note: expected type `i32`\n              found type `()`\n\n"}
[01:07:36] {"message":"the trait bound `(): std::ops::Try` is not satisfied","code":{"code":"E0277","explanation":"\nYou tried to use a type which doesn't implement some trait in a place which\nexpected that trait. Erroneous code example:\n\n```compile_fail,E0277\n// here we declare the Foo trait with a bar method\ntrait Foo {\n    fn bar(&self);\n}\n\n// we now declare a function which takes an object implementing the Foo trait\nfn some_func<T: Foo>(foo: T) {\n    foo.bar();\n}\n\nfn main() {\n    // we now call the method with the i32 type, which doesn't implement\n    // the Foo trait\n    some_func(5i32); // error: the trait bound `i32 : Foo` is not satisfied\n}\n```\n\nIn order to fix this error, verify that the type you're using does implement\nthe trait. Example:\n\n```\ntrait Foo {\n    fn bar(&self);\n}\n\nfn some_func<T: Foo>(foo: T) {\n    foo.bar(); // we can now use this method since i32 implements the\n               // Foo trait\n}\n\n// we implement the trait on the i32 type\nimpl Foo for i32 {\n    fn bar(&self) {}\n}\n\nfn main() {\n    some_func(5i32); // ok!\n}\n```\n\nOr in a generic context, an erroneous code example would look like:\n\n```compile_fail,E0277\nfn some_func<T>(foo: T) {\n    println!(\"{:?}\", foo); // error: the trait `core::fmt::Debug` is not\n                           //        implemented for the type `T`\n}\n\nfn main() {\n    // We now call the method with the i32 type,\n    // which *does* implement the Debug trait.\n    some_func(5i32);\n}\n```\n\nNote that the error here is in the definition of the generic function: Although\nwe only call it with a parameter that does implement `Debug`, the compiler\nstill rejects the function: It must work with all possible input types. In\norder to make this example compile, we need to restrict the generic type we're\naccepting:\n\n```\nuse std::fmt;\n\n// Restrict the input type to types that implement Debug.\nfn some_func<T: fmt::Debug>(foo: T) {\n    println!(\"{:?}\", foo);\n}\n\nfn main() {\n    // Calling the method is still fine, as i32 implements Debug.\n    some_func(5i32);\n\n    // This would fail to compile now:\n    // struct WithoutDebug;\n    // some_func(WithoutDebug);\n}\n```\n\nRust only looks at the signature of the called function, as such it must\nalready specify all requirements that will be used for every type parameter.\n"},"level":"error","spans":[{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":393,"byte_end":396,"line_start":17,"line_end":17,"column_start":23,"column_end":26,"is_primary":true,"text":[{"text":"    let res: () = try { }; //~ the trait bound `(): std::ops::Try` is not satisfied","highlight_start":23,"highlight_end":26}],"label":"the trait `std::ops::Try` is not implemented for `()`","suggested_replacement":null,"suggestion_applicability":null,"expansion":{"span":{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":393,"byte_end":396,"line_start":17,"line_end":17,"column_start":23,"column_end":26,"is_primary":false,"text":[{"text":"    let res: () = try { }; //~ the trait bound `(): std::ops::Try` is not satisfied","highlight_start":23,"highlight_end":26}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null},"macro_decl_name":"desugaring of `try block`","def_site_span":{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":393,"byte_end":396,"line_start":17,"line_end":17,"column_start":23,"column_end":26,"is_primary":false,"text":[{"text":"    let res: () = try { }; //~ the trait bound `(): std::ops::Try` is not satisfied","highlight_start":23,"highlight_end":26}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null}}}],"children":[{"message":"required by `std::ops::Try::from_ok`","code":null,"level":"note","spans":[],"children":[],"rendered":null}],"rendered":"error[E0277]: the trait bound `(): std::ops::Try` is not satisfied\n  --> /checkout/src/test/ui/try-block/try-block-bad-type.rs:17:23\n   |\nLL |     let res: () = try { }; //~ the trait bound `(): std::ops::Try` is not satisfied\n   |                       ^^^ the trait `std::ops::Try` is not implemented for `()`\n   |\n   = note: required by `std::ops::Try::from_ok`\n\n"}
[01:07:36] {"message":"the trait bound `i32: std::ops::Try` is not satisfied","code":{"code":"E0277","explanation":"\nYou tried to use a type which doesn't implement some trait in a place which\nexpected that trait. Erroneous code example:\n\n```compile_fail,E0277\n// here we declare the Foo trait with a bar method\ntrait Foo {\n    fn bar(&self);\n}\n\n// we now declare a function which takes an object implementing the Foo trait\nfn some_func<T: Foo>(foo: T) {\n    foo.bar();\n}\n\nfn main() {\n    // we now call the method with the i32 type, which doesn't implement\n    // the Foo trait\n    some_func(5i32); // error: the trait bound `i32 : Foo` is not satisfied\n}\n```\n\nIn order to fix this error, verify that the type you're using does implement\nthe trait. Example:\n\n```\ntrait Foo {\n    fn bar(&self);\n}\n\nfn some_func<T: Foo>(foo: T) {\n    foo.bar(); // we can now use this method since i32 implements the\n               // Foo trait\n}\n\n// we implement the trait on the i32 type\nimpl Foo for i32 {\n    fn bar(&self) {}\n}\n\nfn main() {\n    some_func(5i32); // ok!\n}\n```\n\nOr in a generic context, an erroneous code example would look like:\n\n```compile_fail,E0277\nfn some_func<T>(foo: T) {\n    println!(\"{:?}\", foo); // error: the trait `core::fmt::Debug` is not\n                           //        implemented for the type `T`\n}\n\nfn main() {\n    // We now call the method with the i32 type,\n    // which *does* implement the Debug trait.\n    some_func(5i32);\n}\n```\n\nNote that the error here is in the definition of the generic function: Although\nwe only call it with a parameter that does implement `Debug`, the compiler\nstill rejects the function: It must work with all possible input types. In\norder to make this example compile, we need to restrict the generic type we're\naccepting:\n\n```\nuse std::fmt;\n\n// Restrict the input type to types that implement Debug.\nfn some_func<T: fmt::Debug>(foo: T) {\n    println!(\"{:?}\", foo);\n}\n\nfn main() {\n    // Calling the method is still fine, as i32 implements Debug.\n    some_func(5i32);\n\n    // This would fail to compile now:\n    // struct WithoutDebug;\n    // some_func(WithoutDebug);\n}\n```\n\nRust only looks at the signature of the called function, as such it must\nalready specify all requirements that will be used for every type parameter.\n"},"level":"error","spans":[{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":479,"byte_end":484,"line_start":19,"line_end":19,"column_start":24,"column_end":29,"is_primary":true,"text":[{"text":"    let res: i32 = try { 5 }; //~ ERROR the trait bound `i32: std::ops::Try` is not satisfied","highlight_start":24,"highlight_end":29}],"label":"the trait `std::ops::Try` is not implemented for `i32`","suggested_replacement":null,"suggestion_applicability":null,"expansion":{"span":{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":479,"byte_end":484,"line_start":19,"line_end":19,"column_start":24,"column_end":29,"is_primary":false,"text":[{"text":"    let res: i32 = try { 5 }; //~ ERROR the trait bound `i32: std::ops::Try` is not satisfied","highlight_start":24,"highlight_end":29}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null},"macro_decl_name":"desugaring of `try block`","def_site_span":{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":479,"byte_end":484,"line_start":19,"line_end":19,"column_start":24,"column_end":29,"is_primary":false,"text":[{"text":"    let res: i32 = try { 5 }; //~ ERROR the trait bound `i32: std::ops::Try` is not satisfied","highlight_start":24,"highlight_end":29}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null}}}],"children":[{"message":"required by `std::ops::Try::from_ok`","code":null,"level":"note","spans":[],"children":[],"rendered":null}],"rendered":"error[E0277]: the trait bound `i32: std::ops::Try` is not satisfied\n  --> /checkout/src/test/ui/try-block/try-block-bad-type.rs:19:24\n   |\nLL |     let res: i32 = try { 5 }; //~ ERROR the trait bound `i32: std::ops::Try` is not satisfied\n   |                        ^^^^^ the trait `std::ops::Try` is not implemented for `i32`\n   |\n   = note: required by `std::ops::Try::from_ok`\n\n"}
[01:07:36] {"message":"aborting due to 5 previous errors","code":null,"level":"error","spans":[],"children":[],"rendered":"error: aborting due to 5 previous errors\n\n"}
[01:07:36] {"message":"Some errors occurred: E0271, E0277.","code":null,"level":"","spans":[],"children":[],"rendered":"Some errors occurred: E0271, E0277.\n"}
[01:07:36] 
[01:07:36] ------------------------------------------
[01:07:36] 
[01:07:36] thread '[ui] ui/try-block/try-block-bad-type.rs' panicked at 'explicit panic', src/tools/compiletest/src/runtest.rs:3245:9
---
[01:07:36] 
[01:07:36] thread 'main' panicked at 'Some tests failed', src/tools/compiletest/src/main.rs:495:22
[01:07:36] 
[01:07:36] 
[01:07:36] 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/x86_64-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-x86_64-unknown-linux-gnu" "--mode" "ui" "--target" "x86_64-unknown-linux-gnu" "--host" "x86_64-unknown-linux-gnu" "--llvm-filecheck" "/usr/lib/llvm-6.0/bin/FileCheck" "--host-rustcflags" "-Crpath -O -Zunstable-options  -Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers" "--target-rustcflags" "-Crpath -O -Zunstable-options  -Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers" "--docck-python" "/usr/bin/python2.7" "--lldb-python" "/usr/bin/python2.7" "--gdb" "/usr/bin/gdb" "--quiet" "--llvm-version" "6.0.0\n" "--system-llvm" "--cc" "" "--cxx" "" "--cflags" "" "--llvm-components" "" "--llvm-cxxflags" "" "--adb-path" "adb" "--adb-test-dir" "/data/tmp/work" "--android-cross-path" "" "--color" "always"
The command "stamp sh -x -c "$RUN_SCRIPT"" exited with 2.
travis_time:start:019fcfa8
$ date && (curl -fs --head https://google.com | grep ^Date: | sed 's/Date: //g' || true)
Wed Jan  9 19:57:44 UTC 2019
---
travis_time:end:0e47c818:start=1547063865844679373,finish=1547063865850683569,duration=6004196
travis_fold:end:after_failure.3
travis_fold:start:after_failure.4
travis_time:start:1d1355fb
$ ln -s . checkout && for CORE in obj/cores/core.*; do EXE=$(echo $CORE | sed 's|obj/cores/core\.[0-9]*\.!checkout!\(.*\)|\1|;y|!|/|'); if [ -f "$EXE" ]; then printf travis_fold":start:crashlog\n\033[31;1m%s\033[0m\n" "$CORE"; gdb --batch -q -c "$CORE" "$EXE" -iex 'set auto-load off' -iex 'dir src/' -iex 'set sysroot .' -ex bt -ex q; echo travis_fold":"end:crashlog; fi; done || true
travis_fold:end:after_failure.4
travis_fold:start:after_failure.5
travis_time:start:095f5020
travis_time:start:095f5020
$ cat ./obj/build/x86_64-unknown-linux-gnu/native/asan/build/lib/asan/clang_rt.asan-dynamic-i386.vers || true
cat: ./obj/build/x86_64-unknown-linux-gnu/native/asan/build/lib/asan/clang_rt.asan-dynamic-i386.vers: No such file or directory
travis_fold:end:after_failure.5
travis_fold:start:after_failure.6
travis_time:start:02c4d506
$ dmesg | grep -i kill

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @TimNN. (Feature Requests)

scottmcm · 2019-01-09T22:27:38Z

I was in favour of not having these before, but there have certainly been enough requests that if these are trivial to add, they might as well just exist.

Amanieu · 2019-01-10T01:43:06Z

I'm in favor of this since it would make NonZero* consistent with Atomic*, which has both signed and unsigned variants even though you could get away with just one.

rfcbot · 2019-01-10T05:51:26Z

🔔 This is now entering its final comment period, as per the review above. 🔔

KamilaBorowska

I think it would make sense to have some tests for NonZeroI* types. Check whether they can store negative values without causing undefined behaviour, and so on.

Xaeroxe · 2019-01-10T15:51:18Z

Thank you for this! This is the happiest I've ever been to deprecate my own code.

rust-highfive · 2019-01-10T17:32:04Z

The job x86_64-gnu-llvm-6.0 of your PR failed on Travis (raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.

travis_fold:start:worker_info
Worker information
hostname: 2b5a4b35-2d7e-4056-a526-a3b927f0331d@1.production-2-worker-com-gce-btlt
version: v6.2.0 https://github.com/travis-ci/worker/tree/5e5476e01646095f48eec13196fdb3faf8f5cbf7
startup: 6.815506732s
travis_fold:end:worker_info
travis_fold:start:system_info
Build system information
---
travis_time:end:2865d998:start=1547137555748345823,finish=1547137556625158916,duration=876813093
$ git checkout -qf FETCH_HEAD
travis_fold:end:git.checkout

Encrypted environment variables have been removed for security reasons.
See https://docs.travis-ci.com/user/pull-requests/#pull-requests-and-security-restrictions
$ export SCCACHE_BUCKET=rust-lang-ci-sccache2
$ export SCCACHE_REGION=us-west-1
Setting environment variables from .travis.yml
$ export IMAGE=x86_64-gnu-llvm-6.0
---
[00:04:36] 71  |                           Some(unsafe { $Ty(n) })
[00:04:36]     |                                ^^^^^^ unnecessary `unsafe` block
[00:04:36] ...
[00:04:36] 100 | / nonzero_integers! {
[00:04:36] 101 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU8(u8);
[00:04:36] 102 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU16(u16);
[00:04:36] 103 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU32(u32);
[00:04:36] ...   |
[00:04:36] 112 | |     #[stable(feature = "signed_nonzero", since = "1.33.0")] NonZeroIsize(isize);
[00:04:36]     | |_- in this macro invocation
[00:04:36]     |
[00:04:36]     = note: #[warn(unused_unsafe)] on by default
[00:04:36] 
[00:04:36] 
[00:04:36] warning: unnecessary `unsafe` block
[00:04:36]    --> src/libcore/num/mod.rs:71:30
[00:04:36]     |
[00:04:36] 71  |                           Some(unsafe { $Ty(n) })
[00:04:36]     |                                ^^^^^^ unnecessary `unsafe` block
[00:04:36] ...
[00:04:36] 100 | / nonzero_integers! {
[00:04:36] 101 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU8(u8);
[00:04:36] 102 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU16(u16);
[00:04:36] 103 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU32(u32);
[00:04:36] ...   |
[00:04:36] 112 | |     #[stable(feature = "signed_nonzero", since = "1.33.0")] NonZeroIsize(isize);
[00:04:36]     | |_- in this macro invocation
[00:04:36] 
[00:04:36] warning: unnecessary `unsafe` block
[00:04:36]     --> src/libcore/ptr.rs:2785:18
---
[00:04:36] 50  |                   #[rustc_layout_scalar_valid_range_start(1)]
[00:04:36]     |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[00:04:36] ...
[00:04:36] 100 | / nonzero_integers! {
[00:04:36] 101 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU8(u8);
[00:04:36] 102 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU16(u16);
[00:04:36] 103 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU32(u32);
[00:04:36] ...   |
[00:04:36] 112 | |     #[stable(feature = "signed_nonzero", since = "1.33.0")] NonZeroIsize(isize);
[00:04:36]     | |_- in this macro invocation
[00:04:36]     |
[00:04:36]     = note: #[warn(unused_attributes)] on by default
[00:04:36] 
[00:04:36] 
[00:04:36] warning: unused attribute
[00:04:36]    --> src/libcore/num/mod.rs:50:17
[00:04:36]     |
[00:04:36] 50  |                   #[rustc_layout_scalar_valid_range_start(1)]
[00:04:36]     |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[00:04:36] ...
[00:04:36] 100 | / nonzero_integers! {
[00:04:36] 101 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU8(u8);
[00:04:36] 102 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU16(u16);
[00:04:36] 103 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU32(u32);
[00:04:36] ...   |
[00:04:36] 112 | |     #[stable(feature = "signed_nonzero", since = "1.33.0")] NonZeroIsize(isize);
[00:04:36]     | |_- in this macro invocation
[00:04:36] 
[00:04:36] warning: unused attribute
[00:04:36]     --> src/libcore/ptr.rs:2720:1
---
[01:05:29] .................................................................................................... 4600/5298
[01:05:32] .................................................................................................... 4700/5298
[01:05:35] .................................................................................................... 4800/5298
[01:05:39] .................................................................................................... 4900/5298
[01:05:43] ..............................................F..................................................... 5000/5298
[01:05:49] .................................................................................................... 5200/5298
[01:05:51] .....................................i............................................................
[01:05:51] failures:
[01:05:51] 
[01:05:51] 
[01:05:51] ---- [ui] ui/try-block/try-block-bad-type.rs stdout ----
[01:05:51] diff of stderr:
[01:05:51] 
[01:05:51] 5    |         ^^^^^^^^ the trait `std::convert::From<&str>` is not implemented for `i32`
[01:05:51] 7    = help: the following implementations were found:
[01:05:51] 7    = help: the following implementations were found:
[01:05:51] -              <i32 as std::convert::From<bool>>
[01:05:51] +              <i32 as std::convert::From<core::num::NonZer--------
[01:05:51] {"message":"the trait bound `i32: std::convert::From<&str>` is not satisfied","code":{"code":"E0277","explanation":"\nYou tried to use a type which doesn't implement some trait in a place which\nexpected that trait. Erroneous code example:\n\n```compile_fail,E0277\n// here we declare the Foo trait with a bar method\ntrait Foo {\n    fn bar(&self);\n}\n\n// we now declare a function which takes an object implementing the Foo trait\nfn some_func<T: Foo>(foo: T) {\n    foo.bar();\n}\n\nfn main() {\n    // we now call the method with the i32 type, which doesn't implement\n    // the Foo trait\n    some_func(5i32); // error: the trait bound `i32 : Foo` is not satisfied\n}\n```\n\nIn order to fix this error, verify that the type you're using does implement\nthe trait. Example:\n\n```\ntrait Foo {\n    fn bar(&self);\n}\n\nfn some_func<T: Foo>(foo: T) {\n    foo.bar(); // we can now use this method since i32 implements the\n               // Foo trait\n}\n\n// we implement the trait on the i32 type\nimpl Foo for i32 {\n    fn bar(&self) {}\n}\n\nfn main() {\n    some_func(5i32); // ok!\n}\n```\n\nOr in a generic context, an erroneous code example would look like:\n\n```compile_fail,E0277\nfn some_func<T>(foo: T) {\n    println!(\"{:?}\", foo); // error: the trait `core::fmt::Debug` is not\n                           //        implemented for the type `T`\n}\n\nfn main() {\n    // We now call the method with the i32 type,\n    // which *does* implement the Debug trait.\n    some_func(5i32);\n}\n```\n\nNote that the error here is in the definition of the generic function: Although\nwe only call it with a parameter that does implement `Debug`, the compiler\nstill rejects the function: It must work with all possible input types. In\norder to make this example compile, we need to restrict the generic type we're\naccepting:\n\n```\nuse std::fmt;\n\n// Restrict the input type to types that implement Debug.\nfn some_func<T: fmt::Debug>(foo: T) {\n    println!(\"{:?}\", foo);\n}\n\nfn main() {\n    // Calling the method is still fine, as i32 implements Debug.\n    some_func(5i32);\n\n    // This would fail to compile now:\n    // struct WithoutDebug;\n    // some_func(WithoutDebug);\n}\n```\n\nRust only looks at the signature of the called function, as such it must\nalready specify all requirements that will be used for every type parameter.\n"},"level":"error","spans":[{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":121,"byte_end":129,"line_start":7,"line_end":7,"column_start":9,"column_end":17,"is_primary":true,"text":[{"text":"        Err(\"\")?; //~ ERROR the trait bound `i32: std::convert::From<&str>` is not satisfied","highlight_start":9,"highlight_end":17}],"label":"the trait `std::convert::From<&str>` is not implemented for `i32`","suggested_replacement":null,"suggestion_applicability":null,"expansion":null}],"children":[{"message":"the following implementations were found:\n  <i32 as std::convert::From<core::num::NonZeroI32>>\n  <i32 as std::convert::From<i16>>\n  <i32 as std::convert::From<i8>>\n  <i32 as std::convert::From<u8>>\nand 2 others","code":null,"level":"help","spans":[],"children":[],"rendered":null},{"message":"required by `std::convert::From::from`","code":null,"level":"note","spans":[],"children":[],"rendered":null}],"rendered":"error[E0277]: the trait bound `i32: std::convert::From<&str>` is not satisfied\n  --> /checkout/src/test/ui/try-block/try-block-bad-type.rs:7:9\n   |\nLL |         Err(\"\")?; //~ ERROR the trait bound `i32: std::convert::From<&str>` is not satisfied\n   |         ^^^^^^^^ the trait `std::convert::From<&str>` is not implemented for `i32`\n   |\n   = help: the following implementations were found:\n             <i32 as std::convert::From<core::num::NonZeroI32>>\n             <i32 as std::convert::From<i16>>\n             <i32 as std::convert::From<i8>>\n             <i32 as std::convert::From<u8>>\n           and 2 others\n   = note: required by `std::convert::From::from`\n\n"}
[01:05:51] {"message":"type mismatch resolving `<std::result::Result<i32, i32> as std::ops::Try>::Ok == &str`","code":{"code":"E0271","explanation":"\nThis is because of a type mismatch between the associated type of some\ntrait (e.g., `T::Bar`, where `T` implements `trait Quux { type Bar; }`)\nand another type `U` that is required to be equal to `T::Bar`, but is not.\nExamples follow.\n\nHere is a basic example:\n\n```compile_fail,E0271\ntrait Trait { type AssociatedType; }\n\nfn foo<T>(t: T) where T: Trait<AssociatedType=u32> {\n    println!(\"in foo\");\n}\n\nimpl Trait for i8 { type AssociatedType = &'static str; }\n\nfoo(3_i8);\n```\n\nHere is that same example again, with some explanatory comments:\n\n```compile_fail,E0271\ntrait Trait { type AssociatedType; }\n\nfn foo<T>(t: T) where T: Trait<AssociatedType=u32> {\n//                    ~~~~~~~~ ~~~~~~~~~~~~~~~~~~\n//                        |            |\n//         This says `foo` can         |\n//           only be used with         |\n//              some type that         |\n//         implements `Trait`.         |\n//                                     |\n//                             This says not only must\n//                             `T` be an impl of `Trait`\n//                             but also that the impl\n//                             must assign the type `u32`\n//                             to the associated type.\n    println!(\"in foo\");\n}\n\nimpl Trait for i8 { type AssociatedType = &'static str; }\n//~~~~~~~~~~~~~~~   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n//      |                             |\n// `i8` does have                     |\n// implementation                     |\n// of `Trait`...                      |\n//                     ... but it is an implementation\n//                     that assigns `&'static str` to\n//                     the associated type.\n\nfoo(3_i8);\n// Here, we invoke `foo` with an `i8`, which does not satisfy\n// the constraint `<i8 as Trait>::AssociatedType=u32`, and\n// therefore the type-checker complains with this error code.\n```\n\nTo avoid those issues, you have to make the types match correctly.\nSo we can fix the previous examples like this:\n\n```\n// Basic Example:\ntrait Trait { type AssociatedType; }\n\nfn foo<T>(t: T) where T: Trait<AssociatedType = &'static str> {\n    println!(\"in foo\");\n}\n\nimpl Trait for i8 { type AssociatedType = &'static str; }\n\nfoo(3_i8);\n\n// For-Loop Example:\nlet vs = vec![1, 2, 3, 4];\nfor v in &vs {\n    match v {\n        &1 => {}\n        _ => {}\n    }\n}\n```\n"},"level":"error","spans":[{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":270,"byte_end":272,"line_start":12,"line_end":12,"column_start":9,"column_end":11,"is_primary":true,"text":[{"text":"        \"\" //~ ERROR type mismatch","highlight_start":9,"highlight_end":11}],"label":"expected i32, found &str","suggested_replacement":null,"suggestion_applicability":null,"expansion":null}],"children":[{"message":"expected type `i32`\n   found type `&str`","code":null,"level":"note","spans":[],"children":[],"rendered":null}],"rendered":"error[E0271]: type mismatch resolving `<std::result::Result<i32, i32> as std::ops::Try>::Ok == &str`\n  --> /checkout/src/test/ui/try-block/try-block-bad-type.rs:12:9\n   |\nLL |         \"\" //~ ERROR type mismatch\n   |         ^^ expected i32, found &str\n   |\n   = note: expected type `i32`\n              found type `&str`\n\n"}
[01:05:51] {"message":"type mismatch resolving `<std::result::Result<i32, i32> as std::ops::Try>::Ok == ()`","code":{"code":"E0271","explanation":"\nThis is because of a type mismatch between the associated type of some\ntrait (e.g., `T::Bar`, where `T` implements `trait Quux { type Bar; }`)\nand another type `U` that is required to be equal to `T::Bar`, but is not.\nExamples follow.\n\nHere is a basic example:\n\n```compile_fail,E0271\ntrait Trait { type AssociatedType; }\n\nfn foo<T>(t: T) where T: Trait<AssociatedType=u32> {\n    println!(\"in foo\");\n}\n\nimpl Trait for i8 { type AssociatedType = &'static str; }\n\nfoo(3_i8);\n```\n\nHere is that same example again, with some explanatory comments:\n\n```compile_fail,E0271\ntrait Trait { type AssociatedType; }\n\nfn foo<T>(t: T) where T: Trait<AssociatedType=u32> {\n//                    ~~~~~~~~ ~~~~~~~~~~~~~~~~~~\n//                        |            |\n//         This says `foo` can         |\n//           only be used with         |\n//              some type that         |\n//         implements `Trait`.         |\n//                                     |\n//                             This says not only must\n//                             `T` be an impl of `Trait`\n//                             but also that the impl\n//                             must assign the type `u32`\n//                             to the associated type.\n    println!(\"in foo\");\n}\n\nimpl Trait for i8 { type AssociatedType = &'static str; }\n//~~~~~~~~~~~~~~~   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n//      |                             |\n// `i8` does have                     |\n// implementation                     |\n// of `Trait`...                      |\n//                     ... but it is an implementation\n//                     that assigns `&'static str` to\n//                     the associated type.\n\nfoo(3_i8);\n// Here, we invoke `foo` with an `i8`, which does not satisfy\n// the constraint `<i8 as Trait>::AssociatedType=u32`, and\n// therefore the type-checker complains with this error code.\n```\n\nTo avoid those issues, you have to make the types match correctly.\nSo we can fix the previous examples like this:\n\n```\n// Basic Example:\ntrait Trait { type AssociatedType; }\n\nfn foo<T>(t: T) where T: Trait<AssociatedType = &'static str> {\n    println!(\"in foo\");\n}\n\nimpl Trait for i8 { type AssociatedType = &'static str; }\n\nfoo(3_i8);\n\n// For-Loop Example:\nlet vs = vec![1, 2, 3, 4];\nfor v in &vs {\n    match v {\n        &1 => {}\n        _ => {}\n    }\n}\n```\n"},"level":"error","spans":[{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":343,"byte_end":344,"line_start":15,"line_end":15,"column_start":39,"column_end":40,"is_primary":true,"text":[{"text":"    let res: Result<i32, i32> = try { }; //~ ERROR type mismatch","highlight_start":39,"highlight_end":40}],"label":"expected i32, found ()","suggested_replacement":null,"suggestion_applicability":null,"expansion":{"span":{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":341,"byte_end":344,"line_start":15,"line_end":15,"column_start":37,"column_end":40,"is_primary":false,"text":[{"text":"    let res: Result<i32, i32> = try { }; //~ ERROR type mismatch","highlight_start":37,"highlight_end":40}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null},"macro_decl_name":"desugaring of `try block`","def_site_span":{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":341,"byte_end":344,"line_start":15,"line_end":15,"column_start":37,"column_end":40,"is_primary":false,"text":[{"text":"    let res: Result<i32, i32> = try { }; //~ ERROR type mismatch","highlight_start":37,"highlight_end":40}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null}}}],"children":[{"message":"expected type `i32`\n   found type `()`","code":null,"level":"note","spans":[],"children":[],"rendered":null}],"rendered":"error[E0271]: type mismatch resolving `<std::result::Result<i32, i32> as std::ops::Try>::Ok == ()`\n  --> /checkout/src/test/ui/try-block/try-block-bad-type.rs:15:39\n   |\nLL |     let res: Result<i32, i32> = try { }; //~ ERROR type mismatch\n   |                                       ^ expected i32, found ()\n   |\n   = note: expected type `i32`\n              found type `()`\n\n"}
[01:05:51] {"message":"the trait bound `(): std::ops::Try` is not satisfied","code":{"code":"E0277","explanation":"\nYou tried to use a type which doesn't implement some trait in a place which\nexpected that trait. Erroneous code example:\n\n```compile_fail,E0277\n// here we declare the Foo trait with a bar method\ntrait Foo {\n    fn bar(&self);\n}\n\n// we now declare a function which takes an object implementing the Foo trait\nfn some_func<T: Foo>(foo: T) {\n    foo.bar();\n}\n\nfn main() {\n    // we now call the method with the i32 type, which doesn't implement\n    // the Foo trait\n    some_func(5i32); // error: the trait bound `i32 : Foo` is not satisfied\n}\n```\n\nIn order to fix this error, verify that the type you're using does implement\nthe trait. Example:\n\n```\ntrait Foo {\n    fn bar(&self);\n}\n\nfn some_func<T: Foo>(foo: T) {\n    foo.bar(); // we can now use this method since i32 implements the\n               // Foo trait\n}\n\n// we implement the trait on the i32 type\nimpl Foo for i32 {\n    fn bar(&self) {}\n}\n\nfn main() {\n    some_func(5i32); // ok!\n}\n```\n\nOr in a generic context, an erroneous code example would look like:\n\n```compile_fail,E0277\nfn some_func<T>(foo: T) {\n    println!(\"{:?}\", foo); // error: teclare the Foo trait with a bar method\ntrait Foo {\n    fn bar(&self);\n}\n\n// we now declare a function which takes an object implementing the Foo trait\nfn some_func<T: Foo>(foo: T) {\n    foo.bar();\n}\n\nfn main() {\n    // we now call the method with the i32 type, which doesn't implement\n    // the Foo trait\n    some_func(5i32); // error: the trait bound `i32 : Foo` is not satisfied\n}\n```\n\nIn order to fix this error, verify that the type you're using does implement\nthe trait. Example:\n\n```\ntrait Foo {\n    fn bar(&self);\n}\n\nfn some_func<T: Foo>(foo: T) {\n    foo.bar(); // we can now use this method since i32 implements the\n               // Foo trait\n}\n\n// we implement the trait on the i32 type\nimpl Foo for i32 {\n    fn bar(&self) {}\n}\n\nfn main() {\n    some_func(5i32); // ok!\n}\n```\n\nOr in a generic context, an erroneous code example would look like:\n\n```compile_fail,E0277\nfn some_func<T>(foo: T) {\n    println!(\"{:?}\", foo); // error: the trait `core::fmt::Debug` is not\n                           //        implemented for the type `T`\n}\n\nfn main() {\n    // We now call the method with the i32 type,\n    // which *does* implement the Debug trait.\n    some_func(5i32);\n}\n```\n\nNote that the error here is in the definition of the generic function: Although\nwe only call it with a parameter that does implement `Debug`, the compiler\nstill rejects the function: It must work with all possible input types. In\norder to make this example compile, we need to restrict the generic type we're\naccepting:\n\n```\nuse std::fmt;\n\n// Restrict the input type to types that implement Debug.\nfn some_func<T: fmt::Debug>(foo: T) {\n    println!(\"{:?}\", foo);\n}\n\nfn main() {\n    // Calling the method is still fine, as i32 implements Debug.\n    some_func(5i32);\n\n    // This would fail to compile now:\n    // struct WithoutDebug;\n    // some_func(WithoutDebug);\n}\n```\n\nRust only looks at the signature of the called function, as such it must\nalready specify all requirements that will be used for every type parameter.\n"},"level":"error","spans":[{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":479,"byte_end":484,"line_start":19,"line_end":19,"column_start":24,"column_end":29,"is_primary":true,"text":[{"text":"    let res: i32 = try { 5 }; //~ ERROR the trait bound `i32: std::ops::Try` is not satisfied","highlight_start":24,"highlight_end":29}],"label":"the trait `std::ops::Try` is not implemented for `i32`","suggested_replacement":null,"suggestion_applicability":null,"expansion":{"span":{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":479,"byte_end":484,"line_start":19,"line_end":19,"column_start":24,"column_end":29,"is_primary":false,"text":[{"text":"    let res: i32 = try { 5 }; //~ ERROR the trait bound `i32: std::ops::Try` is not satisfied","highlight_start":24,"highlight_end":29}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null},"macro_decl_name":"desugaring of `try block`","def_site_span":{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":479,"byte_end":484,"line_start":19,"line_end":19,"column_start":24,"column_end":29,"is_primary":false,"text":[{"text":"    let res: i32 = try { 5 }; //~ ERROR the trait bound `i32: std::ops::Try` is not satisfied","highlight_start":24,"highlight_end":29}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null}}}],"children":[{"message":"required by `std::ops::Try::from_ok`","code":null,"level":"note","spans":[],"children":[],"rendered":null}],"rendered":"error[E0277]: the trait bound `i32: std::ops::Try` is not satisfied\n  --> /checkout/src/test/ui/try-block/try-block-bad-type.rs:19:24\n   |\nLL |     let res: i32 = try { 5 }; //~ ERROR the trait bound `i32: std::ops::Try` is not satisfied\n   |                        ^^^^^ the trait `std::ops::Try` is not implemented for `i32`\n   |\n   = note: required by `std::ops::Try::from_ok`\n\n"}
[01:05:51] {"message":"aborting due to 5 previous errors","code":null,"level":"error","spans":[],"children":[],"rendered":"error: aborting due to 5 previous errors\n\n"}
[01:05:51] {"message":"Some errors occurred: E0271, E0277.","code":null,"level":"","spans":[],"children":[],"rendered":"Some errors occurred: E0271, E0277.\n"}
[01:05:51] 
[01:05:51] ------------------------------------------
[01:05:51] 
[01:05:51] thread '[ui] ui/try-block/try-block-bad-type.rs' panicked at 'explicit panic', src/tools/compiletest/src/runtest.rs:3245:9
---
[01:05:51] 
[01:05:51] thread 'main' panicked at 'Some tests failed', src/tools/compiletest/src/main.rs:495:22
[01:05:51] 
[01:05:51] 
[01:05:51] 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/x86_64-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-x86_64-unknown-linux-gnu" "--mode" "ui" "--target" "x86_64-unknown-linux-gnu" "--host" "x86_64-unknown-linux-gnu" "--llvm-filecheck" "/usr/lib/llvm-6.0/bin/FileCheck" "--host-rustcflags" "-Crpath -O -Zunstable-options  -Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers" "--target-rustcflags" "-Crpath -O -Zunstable-options  -Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers" "--docck-python" "/usr/bin/python2.7" "--lldb-python" "/usr/bin/python2.7" "--gdb" "/usr/bin/gdb" "--quiet" "--llvm-version" "6.0.0\n" "--system-llvm" "--cc" "" "--cxx" "" "--cflags" "" "--llvm-components" "" "--llvm-cxxflags" "" "--adb-path" "adb" "--adb-test-dir" "/data/tmp/work" "--android-cross-path" "" "--color" "always"
[01:05:51] 
[01:05:51] 
[01:05:51] failed to run: /checkout/obj/build/bootstrap/debug/bootstrap test
[01:05:51] Build completed unsuccessfully in 0:04:11
[01:05:51] Build completed unsuccessfully in 0:04:11
[01:05:51] make: *** [check] Error 1
[01:05:51] Makefile:48: recipe for target 'check' failed
The command "stamp sh -x -c "$RUN_SCRIPT"" exited with 2.
travis_time:start:0180ced4
$ date && (curl -fs --head https://google.com | grep ^Date: | sed 's/Date: //g' || true)
Thu Jan 10 17:31:59 UTC 2019
---
travis_time:end:0535b124:start=1547141520598605699,finish=1547141520603683530,duration=5077831
travis_fold:end:after_failure.3
travis_fold:start:after_failure.4
travis_time:start:24edfdc8
$ ln -s . checkout && for CORE in obj/cores/core.*; do EXE=$(echo $CORE | sed 's|obj/cores/core\.[0-9]*\.!checkout!\(.*\)|\1|;y|!|/|'); if [ -f "$EXE" ]; then printf travis_fold":start:crashlog\n\033[31;1m%s\033[0m\n" "$CORE"; gdb --batch -q -c "$CORE" "$EXE" -iex 'set auto-load off' -iex 'dir src/' -iex 'set sysroot .' -ex bt -ex q; echo travis_fold":"end:crashlog; fi; done || true
travis_fold:end:after_failure.4
travis_fold:start:after_failure.5
travis_time:start:01a30b32
travis_time:start:01a30b32
$ cat ./obj/build/x86_64-unknown-linux-gnu/native/asan/build/lib/asan/clang_rt.asan-dynamic-i386.vers || true
cat: ./obj/build/x86_64-unknown-linux-gnu/native/asan/build/lib/asan/clang_rt.asan-dynamic-i386.vers: No such file or directory
travis_fold:end:after_failure.5
travis_fold:start:after_failure.6
travis_time:start:180843ea
$ dmesg | grep -i kill

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @TimNN. (Feature Requests)

SimonSapin · 2019-01-10T23:04:48Z

I’d appreciate some help. Maybe @alexcrichton?

I’m getting errors like

---- num/mod.rs - num::NonZeroI16 (line 33) stdout ----
error[E0412]: cannot find type `NonZeroI16` in module `std::num`
 --> num/mod.rs:35:39
  |
5 | assert_eq!(size_of::<Option<std::num::NonZeroI16>>(), size_of::<i16>());
  |                                       ^^^^^^^^^^ did you mean `NonZeroU16`?

thread 'num/mod.rs - num::NonZeroI16 (line 33)' panicked at 'couldn't compile the test', src/librustdoc/test.rs:321:13

It looks like a newly-added type cannot be found in the doctests of that very type.

Later in the output:

command did not execute successfully: "/home/simon/rust3/build/x86_64-unknown-linux-gnu/stage0/bin/cargo" "test" "--target" "x86_64-unknown-linux-gnu" "-j" "8" "--release" "--features" "panic-unwind backtrace" "--manifest-path" "/home/simon/rust3/src/libstd/Cargo.toml" "-p" "core" "--" "--quiet"
expected success, got: exit code: 101

… which includes stage0. The error would make some sense if the bootstrap compiler’s libcore is used to run the new libcore’s doctests, but why would that be the case when running simply ./x.py test?

rust-highfive · 2019-01-11T00:06:08Z

The job x86_64-gnu-llvm-6.0 of your PR failed on Travis (raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.

travis_time:end:0fe5c89c:start=1547161308643622142,finish=1547161310979617799,duration=2335995657
$ git checkout -qf FETCH_HEAD
travis_fold:end:git.checkout

Encrypted environment variables have been removed for security reasons.
See https://docs.travis-ci.com/user/pull-requests/#pull-requests-and-security-restrictions
$ export SCCACHE_BUCKET=rust-lang-ci-sccache2
$ export SCCACHE_REGION=us-west-1
Setting environment variables from .travis.yml
$ export IMAGE=x86_64-gnu-llvm-6.0
---
    97% |███████████████████████████████▍| 532kB 84.1MB/s eta 0:00:01
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Collecting botocore==1.12.77 (from awscli)
  Downloading https://files.pythonhosted.org/packages/f3/cd/f58bacbfb28d92716bfb7af2a8c5d5230663335b6a5e4d78d8ccdfab469d/botocore-1.12.77-py2.py3-none-any.whl (5.2MB)
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---
[00:04:02] 71  |                           Some(unsafe { $Ty(n) })
[00:04:02]     |                                ^^^^^^ unnecessary `unsafe` block
[00:04:02] ...
[00:04:02] 100 | / nonzero_integers! {
[00:04:02] 101 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU8(u8);
[00:04:02] 102 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU16(u16);
[00:04:02] 103 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU32(u32);
[00:04:02] ...   |
[00:04:02] 112 | |     #[stable(feature = "signed_nonzero", since = "1.33.0")] NonZeroIsize(isize);
[00:04:02]     | |_- in this macro invocation
[00:04:02]     |
[00:04:02]     = note: #[warn(unused_unsafe)] on by default
[00:04:02] 
[00:04:02] 
[00:04:02] warning: unnecessary `unsafe` block
[00:04:02]    --> src/libcore/num/mod.rs:71:30
[00:04:02]     |
[00:04:02] 71  |                           Some(unsafe { $Ty(n) })
[00:04:02]     |                                ^^^^^^ unnecessary `unsafe` block
[00:04:02] ...
[00:04:02] 100 | / nonzero_integers! {
[00:04:02] 101 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU8(u8);
[00:04:02] 102 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU16(u16);
[00:04:02] 103 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU32(u32);
[00:04:02] ...   |
[00:04:02] 112 | |     #[stable(feature = "signed_nonzero", since = "1.33.0")] NonZeroIsize(isize);
[00:04:02]     | |_- in this macro invocation
[00:04:02] 
[00:04:02] warning: unnecessary `unsafe` block
[00:04:02]     --> src/libcore/ptr.rs:2785:18
---
[00:04:02] 50  |                   #[rustc_layout_scalar_valid_range_start(1)]
[00:04:02]     |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[00:04:02] ...
[00:04:02] 100 | / nonzero_integers! {
[00:04:02] 101 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU8(u8);
[00:04:02] 102 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU16(u16);
[00:04:02] 103 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU32(u32);
[00:04:02] ...   |
[00:04:02] 112 | |     #[stable(feature = "signed_nonzero", since = "1.33.0")] NonZeroIsize(isize);
[00:04:02]     | |_- in this macro invocation
[00:04:02]     |
[00:04:02]     = note: #[warn(unused_attributes)] on by default
[00:04:02] 
[00:04:02] 
[00:04:02] warning: unused attribute
[00:04:02]    --> src/libcore/num/mod.rs:50:17
[00:04:02]     |
[00:04:02] 50  |                   #[rustc_layout_scalar_valid_range_start(1)]
[00:04:02]     |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[00:04:02] ...
[00:04:02] 100 | / nonzero_integers! {
[00:04:02] 101 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU8(u8);
[00:04:02] 102 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU16(u16);
[00:04:02] 103 | |     #[stable(feature = "nonzero", since = "1.28.0")] NonZeroU32(u32);
[00:04:02] ...   |
[00:04:02] 112 | |     #[stable(feature = "signed_nonzero", since = "1.33.0")] NonZeroIsize(isize);
[00:04:02]     | |_- in this macro invocation
[00:04:02] 
[00:04:02] warning: unused attribute
[00:04:02]     --> src/libcore/ptr.rs:2720:1
---
[01:03:37] .................................................................................................... 4600/5298
[01:03:40] .................................................................................................... 4700/5298
[01:03:43] .................................................................................................... 4800/5298
[01:03:47] .................................................................................................... 4900/5298
[01:03:51] ..............................................F..................................................... 5000/5298
[01:03:58] .................................................................................................... 5200/5298
[01:04:01] .....................................i............................................................
[01:04:01] failures:
[01:04:01] 
[01:04:01] 
[01:04:01] ---- [ui] ui/try-block/try-block-bad-type.rs stdout ----
[01:04:01] diff of stderr:
[01:04:01] 
[01:04:01] 5    |         ^^^^^^^^ the trait `std::convert::From<&str>` is not implemented for `i32`
[01:04:01] 7    = help: the following implementations were found:
[01:04:01] 7    = help: the following implementations were found:
[01:04:01] -              <i32 as std::convert::From<bool>>
[01:04:01] +              <i32 as std::convert::From<core::num::NonZeroI32>>
[01:04:01] 9              <i32 as std::convert::From<i16>>
[01:04:01] -              <i32 as std::convert::From<u16>>
[01:04:01] +              <i32 as std::convert::From<i8>>
[01:04:01] 11              <i32 as std::convert::From<u8>>
[01:04:01] 13    = note: required by `std::convert::From::from`
[01:04:01] 
[01:04:01] 
[01:04:01] The actual stderr differed from the expected stderr.
[01:04:01] The actual stderr differed from the expected stderr.
[01:04:01] Actual stderr saved to /checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/try-block/try-block-bad-type/try-block-bad-type.stderr
[01:04:01] To update references, rerun the tests and pass the `--bless` flag
[01:04:01] To only update this specific test, also pass `--test-args try-block/try-block-bad-type.rs`
[01:04:01] error: 1 errors occurred comparing output.
[01:04:01] status: exit code: 1
[01:04:01] status: exit code: 1
[01:04:01] command: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/bin/rustc" "/checkout/src/test/ui/try-block/try-block-bad-type.rs" "--target=x86_64-unknown-linux-gnu" "--error-format" "json" "-Zui-testing" "-C" "prefer-dynamic" "-o" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/try-block/try-block-bad-type/a" "-Crpath" "-O" "-Zunstable-options" "-Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers" "--edition" "2018" "-L" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/try-block/try-block-bad-type/auxiliary" "-A" "unused"
[01:04:01] ------------------------------------------
[01:04:01] 
[01:04:01] ------------------------------------------
[01:04:01] stderr:
[01:04:01] stderr:
[01:04:01] ------------------------------------------
[01:04:01] {"message":"the trait bound `i32: std::convert::From<&str>` is not satisfied","code":{"code":"E0277","explanation":"\nYou tried to use a type which doesn't implement some trait in a place which\nexpected that trait. Erroneous code example:\n\n```compile_fail,E0277\n// here we declare the Foo trait with a bar method\ntrait Foo {\n    fn bar(&self);\n}\n\n// we now declare a function which takes an object implementing the Foo trait\nfn some_func<T: Foo>(foo: T) {\n    foo.bar();\n}\n\nfn main() {\n    // we now call the method with the i32 type, which doesn't implement\n    // the Foo trait\n    some_func(5i32); // error: the trait bound `i32 : Foo` is not satisfied\n}\n```\n\nIn order to fix this error, verify that the type you're using does implement\nthe trait. Example:\n\n```\ntrait Foo {\n    fn bar(&self);\n}\n\nfn some_func<T: Foo>(foo: T) {\n    foo.bar(); // we can now use this method since i32 implements the\n               // Foo trait\n}\n\n// we implement the trait on the i32 type\nimpl Foo for i32 {\n    fn bar(&self) {}\n}\n\nfn main() {\n    some_func(5i32); // ok!\n}\n```\n\nOr in a generic context, an erroneous code example would look like:\n\n```compile_fail,E0277\nfn some_func<T>(foo: T) {\n    println!(\"{:?}\", foo); // error: the trait `core::fmt::Debug` is not\n                           //        implemented for the type `T`\n}\n\nfn main() {\n    // We now call the method with the i32 type,\n    // which *does* implement the Debug trait.\n    some_func(5i32);\n}\n```\n\nNote that the error here is in the definition of the generic function: Although\nwe only call it with a parameter that does implement `Debug`, the compiler\nstill rejects the function: It must work with all possible input types. In\norder to make this example compile, we need to restrict the generic type we're\naccepting:\n\n```\nuse std::fmt;\n\n// Restrict the input type to types that implement Debug.\nfn some_func<T: fmt::Debug>(foo: T) {\n    println!(\"{:?}\", foo);\n}\n\nfn main() {\n    // Calling the method is still fine, as i32 implements Debug.\n    some_func(5i32);\n\n    // This would fail to compile now:\n    // struct WithoutDebug;\n    // some_func(WithoutDebug);\n}\n```\n\nRust only looks at the signature of the called function, as such it must\nalready specify all requirements that will be used for every type parameter.\n"},"level":"error","spans":[{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":121,"byte_end":129,"line_start":7,"line_end":7,"column_start":9,"column_end":17,"is_primary":true,"text":[{"text":"        Err(\"\")?; //~ ERROR the trait bound `i32: std::convert::From<&str>` is not satisfied","highlight_start":9,"highlight_end":17}],"label":"the trait `std::convert::From<&str>` is not implemented for `i32`","suggested_replacement":null,"suggestion_applicability":null,"expansion":null}],"children":[{"message":"the following implementations were found:\n  <i32 as std::convert::From<core::num::NonZeroI32>>\n  <i32 as std::convert::From<i16>>\n  <i32 as std::convert::From<i8>>\n  <i32 as std::convert::From<u8>>\nand 2 others","code":null,"level":"help","spans":[],"children":[],"rendered":null},{"message":"required by `std::convert::From::from`","code":null,"level":"note","spans":[],"children":[],"rendered":null}],"rendered":"error[E0277]: the trait bound `i32: std::convert::From<&str>` is not satisfied\n  --> /checkout/src/test/ui/try-block/try-block-bad-type.rs:7:9\n   |\nLL |         Err(\"\")?; //~ ERROR the trait bound `i32: std::convert::From<&str>` is not satisfied\n   |         ^^^^^^^^ the trait `std::convert::From<&str>` is not implemented for `i32`\n   |\n   = help: the following implementations were found:\n             <i32 as std::convert::From<core::num::NonZeroI32>>\n             <i32 as std::convert::From<i16>>\n             <i32 as std::convert::From<i8>>\n             <i32 as std::convert::From<u8>>\n           and 2 others\n   = note: required by `std::convert::From::from`\n\n"}
[01:04:01] {"message":"type mismatch resolving `<std::result::Result<i32, i32> as std::ops::Try>::Ok == &str`","code":{"code":"E0271","explanation":"\nThis is because of a type mismatch between the associated type of some\ntrait (e.g., `T::Bar`, where `T` implements `trait Quux { type Bar; }`)\nand another type `U` that is required to be equal to `T::Bar`, but is not.\nExamples follow.\n\nHere is a basic example:\n\n```compile_fail,E0271\ntrait Trait { type AssociatedType; }\n\nfn foo<T>(t: T) where T: Trait<AssociatedType=u32> {\n    println!(\"in foo\");\n}\n\nimpl Trait for i8 { type AssociatedType = &'static str; }\n\nfoo(3_i8);\n```\n\nHere is that same example again, with some explanatory comments:\n\n```compile_fail,E0271\ntrait Trait { type AssociatedType; }\n\nfn foo<T>(t: T) where T: Trait<AssociatedType=u32> {\n//                    ~~~~~~~~ ~~~~~~~~~~~~~~~~~~\n//                        |            |\n//         This says `foo` can         |\n//           only be used with         |\n//              some type that         |\n//         implements `Trait`.         |\n//                                     |\n//                             This says not only must\n//                             `T` be an impl of `Trait`\n//                             but also that the impl\n//                             must assign the type `u32`\n//                             to the associated type.\n    println!(\"in foo\");\n}\n\nimpl Trait for i8 { type AssociatedType = &'static str; }\n//~~~~~~~~~~~~~~~   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n//      |                             |\n// `i8` does have                     |\n// implementation                     |\n// of `Trait`...                      |\n//                     ... but it is an implementation\n//                     that assigns `&'static str` to\n//                     the associated type.\n\nfoo(3_i8);\n// Here, we invoke `foo` with an `i8`, which does not satisfy\n// the constraint `<i8 as Trait>::AssociatedType=u32`, and\n// therefore the type-checker complains with this error code.\n```\n\nTo avoid those issues, you have to make the types match correctly.\nSo we can fix the previous examples like this:\n\n```\n// Basic Example:\ntrait Trait { type AssociatedType; }\n\nfn foo<T>(t: T) where T: Trait<AssociatedType = &'static str> {\n    println!(\"in foo\");\n}\n\nimpl Trait for i8 { type AssociatedType = &'static str; }\n\nfoo(3_i8);\n\n// For-Loop Example:\nlet vs = vec![1, 2, 3, 4];\nfor v in &vs {\n    match v {\n        &1 => {}\n        _ => {}\n    }\n}\n```\n"},"level":"error","spans":[{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":270,"byte_end":272,"line_start":12,"line_end":12,"column_start":9,"column_end":11,"is_primary":true,"text":[{"text":"        \"\" //~ ERROR type mismatch","highlight_start":9,"highlight_end":11}],"label":"expected i32, found &str","suggested_replacement":null,"suggestion_applicability":null,"expansion":null}],"children":[{"message":"expected type `i32`\n   found type `&str`","code":null,"level":"note","spans":[],"children":[],"rendered":null}],"rendered":"error[E0271]: type mismatch resolving `<std::result::Result<i32, i32> as std::ops::Try>::Ok == &str`\n  --> /checkout/src/test/ui/try-block/try-block-bad-type.rs:12:9\n   |\nLL |         \"\" //~ ERROR type mismatch\n   |         ^^ expected i32, found &str\n   |\n   = note: expected type `i32`\n              found type `&str`\n\n"}
[01:04:01] {"message":"type mismatch resolving `<std::result::Result<i32, i32> as std::ops::Try>::Ok == ()`","code":{"code":"E0271","explanation":"\nThis is because of a type mismatch between the associated type of some\ntrait (e.g., `T::Bar`, where `T` implements `trait Quux { type Bar; }`)\nand another type `U` that is required to be equal to `T::Bar`, but is not.\nExamples follow.\n\nHere is a basic example:\n\n```compile_fail,E0271\ntrait Trait { type AssociatedType; }\n\nfn foo<T>(t: T) where T: Trait<AssociatedType=u32> {\n    println!(\"in foo\");\n}\n\nimpl Trait for i8 { type AssociatedType = &'static str; }\n\nfoo(3_i8);\n```\n\nHere is that same example again, with some explanatory comments:\n\n```compile_fail,E0271\ntrait Trait { type AssociatedType; }\n\nfn foo<T>(t: T) where T: Trait<AssociatedType=u32> {\n//                    ~~~~~~~~ ~~~~~~~~~~~~~~~~~~\n//                        |            |\n//         This says `foo` can         |\n//           only be used with         |\n//              some type that         |\n//         implements `Trait`.         |\n//                                     |\n//                             This says not only must\n//                             `T` be an impl of `Trait`\n//                             but also that the impl\n//                             must assign the type `u32`\n//                             to the associated type.\n    println!(\"in foo\");\n}\n\nimpl Trait for i8 { type AssociatedType = &'static str; }\n//~~~~~~~~~~~~~~~   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n//      |                             |\n// `i8` does have                     |\n// implementation                     |\n// of `Trait`...                      |\n//                     ... but it is an implementation\n//                     that assigns `&'static str` to\n//                     the associated type.\n\nfoo(3_i8);\n// Here, we invoke `foo` with an `i8`, which does not satisfy\n// the constraint `<i8 as Trait>::AssociatedType=u32`, and\n// therefore the type-checker complains with this error code.\n```\n\nTo avoid those issues, you have to make the types match correctly.\nSo we can fix the previous examples like this:\n\n```\n// Basic Example:\ntrait Trait { type AssociatedType; }\n\nfn foo<T>(t: T) where T: Trait<AssociatedType = &'static str> {\n    println!(\"in foo\");\n}\n\nimpl Trait for i8 { type AssociatedType = &'static str; }\n\nfoo(3_i8);\n\n// For-Loop Example:\nlet vs = vec![1, 2, 3, 4];\nfor v in &vs {\n    match v {\n        &1 => {}\n        _ => {}\n    }\n}\n```\n"},"level":"error","spans":[{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":343,"byte_end":344,"line_start":15,"line_end":15,"column_start":39,"column_end":40,"is_primary":true,"text":[{"text":"    let res: Result<i32, i32> = try { }; //~ ERROR type mismatch","highlight_start":39,"highlight_end":40}],"label":"expected i32, found ()","suggested_replacement":null,"suggestion_applicability":null,"expansion":{"span":{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":341,"byte_end":344,"line_start":15,"line_end":15,"column_start":37,"column_end":40,"is_primary":false,"text":[{"text":"    let res: Result<i32, i32> = try { }; //~ ERROR type mismatch","highlight_start":37,"highlight_end":40}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null},"macro_decl_name":"desugaring of `try block`","def_site_span":{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":341,"byte_end":344,"line_start":15,"line_end":15,"column_start":37,"column_end":40,"is_primary":false,"text":[{"text":"    let res: Result<i32, i32> = try { }; //~ ERROR type mismatch","highlight_start":37,"highlight_end":40}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null}}}],"children":[{"message":"expected type `i32`\n   found type `()`","code":null,"level":"note","spans":[],"children":[],"rendered":null}],"rendered":"error[E0271]: type mismatch resolving `<std::result::Result<i32, i32> as std::ops::Try>::Ok == ()`\n  --> /checkout/src/test/ui/try-block/try-block-bad-type.rs:15:39\n   |\nLL |     let res: Result<i32, i32> = try { }; //~ ERROR type mismatch\n   |                                       ^ expected i32, found ()\n   |\n   = note: expected type `i32`\n              found type `()`\n\n"}
[01:04:01] {"message":"the trait bound `(): std::ops::Try` is not satisfied","code":{"code":"E0277","explanation":"\nYou tried to use a type which doesn't implement some trait in a place which\nexpected that trait. Erroneous code example:\n\n```compile_fail,E0277\n// here we declare the Foo trait with a bar method\ntrait Foo {\n    fn bar(&self);\n}\n\n// we now declare a function which takes an object implementing the Foo trait\nfn some_func<T: Foo>(foo: T) {\n    foo.bar();\n}\n\nfn main() {\n    // we now call the method with the i32 type, which doesn't implement\n    // the Foo trait\n    some_func(5i32); // error: the trait bound `i32 : Foo` is not satisfied\n}\n```\n\nIn order to fix this error, verify that the type you're using does implement\nthe trait. Example:\n\n```\ntrait Foo {\n    fn bar(&self);\n}\n\nfn some_func<T: Foo>(foo: T) {\n    foo.bar(); // we can now use this method since i32 implements the\n               // Foo trait\n}\n\n// we implement the trait on the i32 type\nimpl Foo for i32 {\n    fn bar(&self) {}\n}\n\nfn main() {\n    some_func(5i32); // ok!\n}\n```\n\nOr in a generic context, an erroneous code example would look like:\n\n```compile_fail,E0277\nfn some_func<T>(foo: T) {\n    println!(\"{:?}\", foo); // error: the trait `core::fmt::Debug` is not\n                           //        implemented for the type `T`\n}\n\nfn main() {\n    // We now call the method with the i32 type,\n    // which *does* implement the Debug trait.\n    some_func(5i32);\n}\n```\n\nNote that the error here is in the definition of the generic function: Although\nwe only call it with a parameter that does implement `Debug`, the compiler\nstill rejects the function: It must work with all possible input types. In\norder to make this example compile, we need to restrict the generic type we're\naccepting:\n\n```\nuse std::fmt;\n\n// Restrict the input type to types that implement Debug.\nfn some_func<T: fmt::Debug>(foo: T) {\n    println!(\"{:?}\", foo);\n}\n\nfn main() {\n    // Calling the method is still fine, as i32 implements Debug.\n    some_func(5i32);\n\n    // This would fail to compile now:\n    // struct WithoutDebug;\n    // some_func(WithoutDebug);\n}\n```\n\nRust only looks at the signature of the called function, as such it must\nalready specify all requirements that will be used for every type parameter.\n"},"level":"error","spans":[{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":393,"byte_end":396,"line_start":17,"line_end":17,"column_start":23,"column_end":26,"is_primary":true,"text":[{"text":"    let res: () = try { }; //~ the trait bound `(): std::ops::Try` is not satisfied","highlight_start":23,"highlight_end":26}],"label":"the trait `std::ops::Try` is not implemented for `()`","suggested_replacement":null,"suggestion_applicability":null,"expansion":{"span":{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":393,"byte_end":396,"line_start":17,"line_end":17,"column_start":23,"column_end":26,"is_primary":false,"text":[{"text":"    let res: () = try { }; //~ the trait bound `(): std::ops::Try` is not satisfied","highlight_start":23,"highlight_end":26}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null},"macro_decl_name":"desugaring of `try block`","def_site_span":{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":393,"byte_end":396,"line_start":17,"line_end":17,"column_start":23,"column_end":26,"is_primary":false,"text":[{"text":"    let res: () = try { }; //~ the trait bound `(): std::ops::Try` is not satisfied","highlight_start":23,"highlight_end":26}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null}}}],"children":[{"message":"required by `std::ops::Try::from_ok`","code":null,"level":"note","spans":[],"children":[],"rendered":null}],"rendered":"error[E0277]: the trait bound `(): std::ops::Try` is not satisfied\n  --> /checkout/src/test/ui/try-block/try-block-bad-type.rs:17:23\n   |\nLL |     let res: () = try { }; //~ the trait bound `(): std::ops::Try` is not satisfied\n   |                       ^^^ the trait `std::ops::Try` is not implemented for `()`\n   |\n   = note: required by `std::ops::Try::from_ok`\n\n"}
[01:04:01] {"message":"the trait bound `i32: std::ops::Try` is not satisfied","code":{"code":"E0277","explanation":"\nYou tried to use a type which doesn't implement some trait in a place which\nexpected that trait. Erroneous code example:\n\n```compile_fail,E0277\n// here we declare the Foo trait with a bar method\ntrait Foo {\n    fn bar(&self);\n}\n\n// we now declare a function which takes an object implementing the Foo trait\nfn some_func<T: Foo>(foo: T) {\n    foo.bar();\n}\n\nfn main() {\n    // we now call the method with the i32 type, which doesn't implement\n    // the Foo trait\n    some_func(5i32); // error: the trait bound `i32 : Foo` is not satisfied\n}\n```\n\nIn order to fix this error, verify that the type you're using does implement\nthe trait. Example:\n\n```\ntrait Foo {\n    fn bar(&self);\n}\n\nfn some_func<T: Foo>(foo: T) {\n    foo.bar(); // we can now use this method since i32 implements the\n               // Foo trait\n}\n\n// we implement the trait on the i32 type\nimpl Foo for i32 {\n    fn bar(&self) {}\n}\n\nfn main() {\n    some_func(5i32); // ok!\n}\n```\n\nOr in a generic context, an erroneous code example would look like:\n\n```compile_fail,E0277\nfn some_func<T>(foo: T) {\n    println!(\"{:?}\", foo); // error: the trait `core::fmt::Debug` is not\n                           //        implemented for the type `T`\n}\n\nfn main() {\n    // We now call the method with the i32 type,\n    // which *does* implement the Debug trait.\n    some_func(5i32);\n}\n```\n\nNote that the error here is in the definition of the generic function: Although\nwe only call it with a parameter that does implement `Debug`, the compiler\nstill rejects the function: It must work with all possible input types. In\norder to make this example compile, we need to restrict the generic type we're\naccepting:\n\n```\nuse std::fmt;\n\n// Restrict the input type to types that implement Debug.\nfn some_func<T: fmt::Debug>(foo: T) {\n    println!(\"{:?}\", foo);\n}\n\nfn main() {\n    // Calling the method is still fine, as i32 implements Debug.\n    some_func(5i32);\n\n    // This would fail to compile now:\n    // struct WithoutDebug;\n    // some_func(WithoutDebug);\n}\n```\n\nRust only looks at the signature of the called function, as such it must\nalready specify all requirements that will be used for every type parameter.\n"},"level":"error","spans":[{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":479,"byte_end":484,"line_start":19,"line_end":19,"column_start":24,"column_end":29,"is_primary":true,"text":[{"text":"    let res: i32 = try { 5 }; //~ ERROR the trait bound `i32: std::ops::Try` is not satisfied","highlight_start":24,"highlight_end":29}],"label":"the trait `std::ops::Try` is not implemented for `i32`","suggested_replacement":null,"suggestion_applicability":null,"expansion":{"span":{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":479,"byte_end":484,"line_start":19,"line_end":19,"column_start":24,"column_end":29,"is_primary":false,"text":[{"text":"    let res: i32 = try { 5 }; //~ ERROR the trait bound `i32: std::ops::Try` is not satisfied","highlight_start":24,"highlight_end":29}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null},"macro_decl_name":"desugaring of `try block`","def_site_span":{"file_name":"/checkout/src/test/ui/try-block/try-block-bad-type.rs","byte_start":479,"byte_end":484,"line_start":19,"line_end":19,"column_start":24,"column_end":29,"is_primary":false,"text":[{"text":"    let res: i32 = try { 5 }; //~ ERROR the trait bound `i32: std::ops::Try` is not satisfied","highlight_start":24,"highlight_end":29}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null}}}],"children":[{"message":"required by `std::ops::Try::from_ok`","code":null,"level":"note","spans":[],"children":[],"rendered":null}],"rendered":"error[E0277]: the trait bound `i32: std::ops::Try` is not satisfied\n  --> /checkout/src/test/ui/try-block/try-block-bad-type.rs:19:24\n   |\nLL |     let res: i32 = try { 5 }; //~ ERROR the trait bound `i32: std::ops::Try` is not satisfied\n   |                        ^^^^^ the trait `std::ops::Try` is not implemented for `i32`\n   |\n   = note: required by `std::ops::Try::from_ok`\n\n"}
[01:04:01] {"message":"aborting due to 5 previous errors","code":null,"level":"error","spans":[],"children":[],"rendered":"error: aborting due to 5 previous errors\n\n"}
[01:04:01] {"message":"Some errors occurred: E0271, E0277.","code":null,"level":"","spans":[],"children":[],"rendered":"Some errors occurred: E0271, E0277.\n"}
[01:04:01] 
[01:04:01] ------------------------------------------
[01:04:01] 
[01:04:01] thread '[ui] ui/try-block/try-block-bad-type.rs' panicked at 'explicit panic', src/tools/compiletest/src/runtest.rs:3245:9
---
[01:04:01] 
[01:04:01] thread 'main' panicked at 'Some tests failed', src/tools/compiletest/src/main.rs:495:22
[01:04:01] 
[01:04:01] 
[01:04:01] 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/x86_64-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-x86_64-unknown-linux-gnu" "--mode" "ui" "--target" "x86_64-unknown-linux-gnu" "--host" "x86_64-unknown-linux-gnu" "--llvm-filecheck" "/usr/lib/llvm-6.0/bin/FileCheck" "--host-rustcflags" "-Crpath -O -Zunstable-options  -Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers" "--target-rustcflags" "-Crpath -O -Zunstable-options  -Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers" "--docck-python" "/usr/bin/python2.7" "--lldb-python" "/usr/bin/python2.7" "--gdb" "/usr/bin/gdb" "--quiet" "--llvm-version" "6.0.0\n" "--system-llvm" "--cc" "" "--cxx" "" "--cflags" "" "--llvm-components" "" "--llvm-cxxflags" "" "--adb-path" "adb" "--adb-test-dir" "/data/tmp/work" "--android-cross-path" "" "--color" "always"
[01:04:01] 
[01:04:01] 
[01:04:01] failed to run: /checkout/obj/build/bootstrap/debug/bootstrap test
[01:04:01] Build completed unsuccessfully in 0:04:07
[01:04:01] Build completed unsuccessfully in 0:04:07
[01:04:01] make: *** [check] Error 1
[01:04:01] Makefile:48: recipe for target 'check' failed
The command "stamp sh -x -c "$RUN_SCRIPT"" exited with 2.
travis_time:start:003155f5
$ date && (curl -fs --head https://google.com | grep ^Date: | sed 's/Date: //g' || true)
Fri Jan 11 00:06:02 UTC 2019
---
travis_time:end:01b4c68e:start=1547165164110832337,finish=1547165164117831544,duration=6999207
travis_fold:end:after_failure.4
travis_fold:start:after_failure.5
travis_time:start:0adc2857
$ cat ./obj/build/x86_64-unknown-linux-gnu/native/asan/build/lib/asan/clang_rt.asan-dynamic-i386.vers || true
cat: ./obj/build/x86_64-unknown-linux-gnu/native/asan/build/lib/asan/clang_rt.asan-dynamic-i386.vers: No such file or directory
travis_fold:end:after_failure.5
travis_fold:start:after_failure.6
travis_time:start:0371f7af
$ dmesg | grep -i kill

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @TimNN. (Feature Requests)

SimonSapin · 2019-01-11T14:01:07Z

Also, ./x.py test --test-args try-block/try-block-bad-type.rs succeeds on my machine, even after a rebase on master, while the same test fails on Travis :/

alexcrichton · 2019-01-11T17:33:07Z

@SimonSapin hm something looks seriously wrong here! I wonder if this is a preexisting compiler bug you're running into. Can you reproduce the travis failure with ./src/ci/docker/run.sh x86_64-gnu-llvm-6.0?

SimonSapin · 2019-01-11T23:38:10Z

@alexcrichton Yes, that command on my machine gives the same output as on Travis.

SimonSapin · 2019-01-12T00:00:32Z

If I tweak src/test/ui/try-block/try-block-bad-type.stderr to get past that error, I can get to the same error as #57475 (comment) in Docker (and presumably on Travis). But then it is ./x.py test on by Ubuntu 18.04 environment that fails try-block-bad-type.

alexcrichton · 2019-01-14T17:29:51Z

Sorry I don't really know what's going on here and what would cause that failure :(

It sounds like it may be a build configuration bug or maybe even a rustc bug, but I wouldn't know for sure without investigating.

alexcrichton · 2019-01-17T16:43:21Z

@bors: r+

bors · 2019-01-17T16:43:22Z

📌 Commit 9be4c76 has been approved by alexcrichton

Add signed num::NonZeroI* types Multiple people have asked for them in rust-lang#49137. Given that the unsigned ones already exist, they are very easy to add and not an additional maintenance burden.

Centril · 2019-01-18T11:36:44Z

Failed in rollup, #57727 (comment).

@bors r-

SimonSapin · 2019-01-18T11:44:01Z

The set of impls printed (or at least their order) in the error[E0277] diagnostic varies between environments. The diff below would (likely) fix the mingw-check CI job like in #57727 (comment), but break x86_64-gnu-llvm-6.0 like in #57475 (comment).

Any idea what’s going on?

diff --git a/src/test/ui/try-block/try-block-bad-type.stderr b/src/test/ui/try-block/try-block-bad-type.stderr
index c2f9e9b52b..4e964f4b83 100644
--- a/src/test/ui/try-block/try-block-bad-type.stderr
+++ b/src/test/ui/try-block/try-block-bad-type.stderr
@@ -5,9 +5,9 @@ LL |         Err("")?; //~ ERROR the trait bound `i32: std::convert::From<&str>`
    |         ^^^^^^^^ the trait `std::convert::From<&str>` is not implemented for `i32`
    |
    = help: the following implementations were found:
-             <i32 as std::convert::From<core::num::NonZeroI32>>
+             <i32 as std::convert::From<bool>>
              <i32 as std::convert::From<i16>>
-             <i32 as std::convert::From<i8>>
+             <i32 as std::convert::From<u16>>
              <i32 as std::convert::From<u8>>
            and 2 others
    = note: required by `std::convert::From::from`

rfcbot · 2019-01-20T05:56:31Z

The final comment period, with a disposition to merge, as per the review above, is now complete.

The diagnostic for this error prints `the following implementations were found` followed by the first N relevant impls, sorted. This commit makes the sort happen before slicing, so that the set of impls being printed is deterministic when the input is not.

SimonSapin · 2019-01-21T17:45:11Z

I pushed a commit that I hope will fix this by removing some non-determinism.

@estebank, could you have a look? Can impl_candidates in report_similar_impl_candidates be very large? With this commit we’re doing some work (normalize and sort) on all of it, not just the first 4 or 5 impls.

estebank · 2019-01-21T18:11:56Z

@SimonSapin it is potentially huge, but in practice I would only imagine this being problematic in the case of generated code. But there are two things: 1) this is only relevant for failing code, so the cost only needs to be "human-speed", we're unlikely to hit problems there in any realistic scenario and 2) we might get away with changing fn all_impls(self, def_id: DefId) -> Vec<DefId> to return an Iterator. That wouldn't be a huge code change, nor performance change, but we're doing iter -> collect -> iter -> filter_map -> collect a few times on the same data :-|

I would go ahead with it, maybe adding a debug statement before and after to be able to check after the fact with a pathological case what the time is.

SimonSapin · 2019-01-21T18:27:24Z

this is only relevant for failing code,

Good point. I think that means it’s probably not worth worrying about.

The other commits have already been reviewed (#57475 (comment)), could you r+ this?

estebank · 2019-01-21T19:28:55Z

@bors r+

bors · 2019-01-21T19:28:55Z

📌 Commit e195ce6 has been approved by estebank

KamilaBorowska · 2019-01-21T20:18:16Z

Sorting can be optimized by using a partial sorting algorithm, changing this from O(N log N) to O(N), but considering this is an error case, it's likely not worth doing.

bors · 2019-01-22T05:42:21Z

⌛ Testing commit e195ce6 with merge 8e9774f...

Add signed num::NonZeroI* types Multiple people have asked for them in #49137. Given that the unsigned ones already exist, they are very easy to add and not an additional maintenance burden.

bors · 2019-01-22T08:24:53Z

☀️ Test successful - checks-travis, status-appveyor
Approved by: estebank
Pushing 8e9774f to master...

SimonSapin added the T-libs-api Relevant to the library API team, which will review and decide on the PR/issue. label Jan 9, 2019

rust-highfive assigned aidanhs Jan 9, 2019

rust-highfive added the S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. label Jan 9, 2019

rfcbot added proposed-final-comment-period Proposed to merge/close by relevant subteam, see T-<team> label. Will enter FCP once signed off. disposition-merge This issue / PR is in PFCP or FCP with a disposition to merge it. labels Jan 9, 2019

SimonSapin mentioned this pull request Jan 9, 2019

Tracking issue for std::num::NonZero* types #49137

Closed

7 tasks

rfcbot added final-comment-period In the final comment period and will be merged soon unless new substantive objections are raised. and removed proposed-final-comment-period Proposed to merge/close by relevant subteam, see T-<team> label. Will enter FCP once signed off. labels Jan 10, 2019

KamilaBorowska suggested changes Jan 10, 2019

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SimonSapin force-pushed the signed branch from 5624341 to c59ea9f Compare January 10, 2019 08:19

SimonSapin force-pushed the signed branch from c59ea9f to 75e15d4 Compare January 10, 2019 16:24

SimonSapin force-pushed the signed branch from 75e15d4 to f1bf970 Compare January 10, 2019 23:00

Centril added the relnotes Marks issues that should be documented in the release notes of the next release. label Jan 11, 2019

KamilaBorowska approved these changes Jan 11, 2019

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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 Jan 17, 2019

Centril mentioned this pull request Jan 18, 2019

Rollup of 22 pull requests #57727

Closed

bors 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-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. labels Jan 18, 2019

rfcbot added finished-final-comment-period The final comment period is finished for this PR / Issue. and removed final-comment-period In the final comment period and will be merged soon unless new substantive objections are raised. labels Jan 20, 2019

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-author Status: This is awaiting some action (such as code changes or more information) from the author. labels Jan 21, 2019

bors merged commit e195ce6 into rust-lang:master Jan 22, 2019

SimonSapin deleted the signed branch January 22, 2019 13:04

Centril mentioned this pull request Feb 11, 2019

Updated RELEASES.md for 1.33.0 #58227

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Centril added this to the 1.34 milestone Apr 27, 2019

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Add signed num::NonZeroI* types #57475

Add signed num::NonZeroI* types #57475

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edited by dtolnay

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bors commented Jan 22, 2019

bors commented Jan 22, 2019

Add signed num::NonZeroI* types #57475

Add signed num::NonZeroI* types #57475

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