2 this method call resolves to `<&{$target} as IntoIterator>::into_iter` (due to backwards compatibility), but will resolve to <{$target} as IntoIterator>::into_iter in Rust 2021
3 .use_iter_suggestion = use `.iter()` instead of `.into_iter()` to avoid ambiguity
4 .remove_into_iter_suggestion = or remove `.into_iter()` to iterate by value
5 .use_explicit_into_iter_suggestion =
6 or use `IntoIterator::into_iter(..)` instead of `.into_iter()` to explicitly iterate by value
8 lint_enum_intrinsics_mem_discriminant =
9 the return value of `mem::discriminant` is unspecified when called with a non-enum type
10 .note = the argument to `discriminant` should be a reference to an enum, but it was passed a reference to a `{$ty_param}`, which is not an enum.
12 lint_enum_intrinsics_mem_variant =
13 the return value of `mem::variant_count` is unspecified when called with a non-enum type
14 .note = the type parameter of `variant_count` should be an enum, but it was instantiated with the type `{$ty_param}`, which is not an enum.
16 lint_expectation = this lint expectation is unfulfilled
17 .note = the `unfulfilled_lint_expectations` lint can't be expected and will always produce this message
18 .rationale = {$rationale}
20 lint_for_loops_over_fallibles =
21 for loop over {$article} `{$ty}`. This is more readably written as an `if let` statement
22 .suggestion = consider using `if let` to clear intent
23 .remove_next = to iterate over `{$recv_snip}` remove the call to `next`
24 .use_while_let = to check pattern in a loop use `while let`
25 .use_question_mark = consider unwrapping the `Result` with `?` to iterate over its contents
27 lint_non_binding_let_on_sync_lock =
28 non-binding let on a synchronization lock
30 lint_non_binding_let_on_drop_type =
31 non-binding let on a type that implements `Drop`
33 lint_non_binding_let_suggestion =
34 consider binding to an unused variable to avoid immediately dropping the value
36 lint_non_binding_let_multi_suggestion =
37 consider immediately dropping the value
39 lint_deprecated_lint_name =
40 lint name `{$name}` is deprecated and may not have an effect in the future.
41 .suggestion = change it to
43 lint_renamed_or_removed_lint = {$msg}
44 .suggestion = use the new name
47 unknown lint: `{$name}`
48 .suggestion = did you mean
50 lint_ignored_unless_crate_specified = {$level}({$name}) is ignored unless specified at crate level
52 lint_unknown_gated_lint =
53 unknown lint: `{$name}`
54 .note = the `{$name}` lint is unstable
56 lint_hidden_unicode_codepoints = unicode codepoint changing visible direction of text present in {$label}
57 .label = this {$label} contains {$count ->
60 } unicode text flow control {$count ->
64 .note = these kind of unicode codepoints change the way text flows on applications that support them, but can cause confusion because they change the order of characters on the screen
65 .suggestion_remove = if their presence wasn't intentional, you can remove them
66 .suggestion_escape = if you want to keep them but make them visible in your source code, you can escape them
67 .no_suggestion_note_escape = if you want to keep them but make them visible in your source code, you can escape them: {$escaped}
69 lint_default_hash_types = prefer `{$preferred}` over `{$used}`, it has better performance
70 .note = a `use rustc_data_structures::fx::{$preferred}` may be necessary
72 lint_query_instability = using `{$query}` can result in unstable query results
73 .note = if you believe this case to be fine, allow this lint and add a comment explaining your rationale
75 lint_tykind_kind = usage of `ty::TyKind::<kind>`
76 .suggestion = try using `ty::<kind>` directly
78 lint_tykind = usage of `ty::TyKind`
79 .help = try using `Ty` instead
81 lint_ty_qualified = usage of qualified `ty::{$ty}`
82 .suggestion = try importing it and using it unqualified
84 lint_lintpass_by_hand = implementing `LintPass` by hand
85 .help = try using `declare_lint_pass!` or `impl_lint_pass!` instead
87 lint_non_existant_doc_keyword = found non-existing keyword `{$keyword}` used in `#[doc(keyword = \"...\")]`
88 .help = only existing keywords are allowed in core/std
90 lint_diag_out_of_impl =
91 diagnostics should only be created in `IntoDiagnostic`/`AddToDiagnostic` impls
93 lint_untranslatable_diag = diagnostics should be created using translatable messages
95 lint_bad_opt_access = {$msg}
97 lint_cstring_ptr = getting the inner pointer of a temporary `CString`
98 .as_ptr_label = this pointer will be invalid
99 .unwrap_label = this `CString` is deallocated at the end of the statement, bind it to a variable to extend its lifetime
100 .note = pointers do not have a lifetime; when calling `as_ptr` the `CString` will be deallocated at the end of the statement because nothing is referencing it as far as the type system is concerned
101 .help = for more information, see https://doc.rust-lang.org/reference/destructors.html
103 lint_identifier_non_ascii_char = identifier contains non-ASCII characters
105 lint_identifier_uncommon_codepoints = identifier contains uncommon Unicode codepoints
107 lint_confusable_identifier_pair = identifier pair considered confusable between `{$existing_sym}` and `{$sym}`
108 .label = this is where the previous identifier occurred
110 lint_mixed_script_confusables =
111 the usage of Script Group `{$set}` in this crate consists solely of mixed script confusables
112 .includes_note = the usage includes {$includes}
113 .note = please recheck to make sure their usages are indeed what you want
115 lint_non_fmt_panic = panic message is not a string literal
116 .note = this usage of `{$name}!()` is deprecated; it will be a hard error in Rust 2021
117 .more_info_note = for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/panic-macro-consistency.html>
118 .supports_fmt_note = the `{$name}!()` macro supports formatting, so there's no need for the `format!()` macro here
119 .supports_fmt_suggestion = remove the `format!(..)` macro call
120 .display_suggestion = add a "{"{"}{"}"}" format string to `Display` the message
122 add a "{"{"}:?{"}"}" format string to use the `Debug` implementation of `{$ty}`
123 .panic_suggestion = {$already_suggested ->
126 } std::panic::panic_any instead
128 lint_non_fmt_panic_unused =
129 panic message contains {$count ->
132 } formatting {$count ->
134 *[other] placeholders
136 .note = this message is not used as a format string when given without arguments, but will be in Rust 2021
137 .add_args_suggestion = add the missing {$count ->
141 .add_fmt_suggestion = or add a "{"{"}{"}"}" format string to use the message literally
143 lint_non_fmt_panic_braces =
144 panic message contains {$count ->
148 .note = this message is not used as a format string, but will be in Rust 2021
149 .suggestion = add a "{"{"}{"}"}" format string to use the message literally
151 lint_non_camel_case_type = {$sort} `{$name}` should have an upper camel case name
152 .suggestion = convert the identifier to upper camel case
153 .label = should have an UpperCamelCase name
155 lint_non_snake_case = {$sort} `{$name}` should have a snake case name
156 .rename_or_convert_suggestion = rename the identifier or convert it to a snake case raw identifier
157 .cannot_convert_note = `{$sc}` cannot be used as a raw identifier
158 .rename_suggestion = rename the identifier
159 .convert_suggestion = convert the identifier to snake case
160 .help = convert the identifier to snake case: `{$sc}`
161 .label = should have a snake_case name
163 lint_non_upper_case_global = {$sort} `{$name}` should have an upper case name
164 .suggestion = convert the identifier to upper case
165 .label = should have an UPPER_CASE name
167 lint_noop_method_call = call to `.{$method}()` on a reference in this situation does nothing
168 .label = unnecessary method call
169 .note = the type `{$receiver_ty}` which `{$method}` is being called on is the same as the type returned from `{$method}`, so the method call does not do anything and can be removed
171 lint_pass_by_value = passing `{$ty}` by reference
172 .suggestion = try passing by value
174 lint_redundant_semicolons =
175 unnecessary trailing {$multiple ->
179 .suggestion = remove {$multiple ->
180 [true] these semicolons
181 *[false] this semicolon
184 lint_drop_trait_constraints =
185 bounds on `{$predicate}` are most likely incorrect, consider instead using `{$needs_drop}` to detect whether a type can be trivially dropped
188 types that do not implement `Drop` can still have drop glue, consider instead using `{$needs_drop}` to detect whether a type is trivially dropped
190 lint_range_endpoint_out_of_range = range endpoint is out of range for `{$ty}`
191 .suggestion = use an inclusive range instead
193 lint_overflowing_bin_hex = literal out of range for `{$ty}`
194 .negative_note = the literal `{$lit}` (decimal `{$dec}`) does not fit into the type `{$ty}`
195 .negative_becomes_note = and the value `-{$lit}` will become `{$actually}{$ty}`
196 .positive_note = the literal `{$lit}` (decimal `{$dec}`) does not fit into the type `{$ty}` and will become `{$actually}{$ty}`
197 .suggestion = consider using the type `{$suggestion_ty}` instead
198 .help = consider using the type `{$suggestion_ty}` instead
200 lint_overflowing_int = literal out of range for `{$ty}`
201 .note = the literal `{$lit}` does not fit into the type `{$ty}` whose range is `{$min}..={$max}`
202 .help = consider using the type `{$suggestion_ty}` instead
204 lint_only_cast_u8_to_char = only `u8` can be cast into `char`
205 .suggestion = use a `char` literal instead
207 lint_overflowing_uint = literal out of range for `{$ty}`
208 .note = the literal `{$lit}` does not fit into the type `{$ty}` whose range is `{$min}..={$max}`
210 lint_overflowing_literal = literal out of range for `{$ty}`
211 .note = the literal `{$lit}` does not fit into the type `{$ty}` and will be converted to `{$ty}::INFINITY`
213 lint_unused_comparisons = comparison is useless due to type limits
215 lint_improper_ctypes = `extern` {$desc} uses type `{$ty}`, which is not FFI-safe
216 .label = not FFI-safe
217 .note = the type is defined here
219 lint_improper_ctypes_opaque = opaque types have no C equivalent
221 lint_improper_ctypes_fnptr_reason = this function pointer has Rust-specific calling convention
222 lint_improper_ctypes_fnptr_help = consider using an `extern fn(...) -> ...` function pointer instead
224 lint_improper_ctypes_tuple_reason = tuples have unspecified layout
225 lint_improper_ctypes_tuple_help = consider using a struct instead
227 lint_improper_ctypes_str_reason = string slices have no C equivalent
228 lint_improper_ctypes_str_help = consider using `*const u8` and a length instead
230 lint_improper_ctypes_dyn = trait objects have no C equivalent
232 lint_improper_ctypes_slice_reason = slices have no C equivalent
233 lint_improper_ctypes_slice_help = consider using a raw pointer instead
235 lint_improper_ctypes_128bit = 128-bit integers don't currently have a known stable ABI
237 lint_improper_ctypes_char_reason = the `char` type has no C equivalent
238 lint_improper_ctypes_char_help = consider using `u32` or `libc::wchar_t` instead
240 lint_improper_ctypes_non_exhaustive = this enum is non-exhaustive
241 lint_improper_ctypes_non_exhaustive_variant = this enum has non-exhaustive variants
243 lint_improper_ctypes_enum_repr_reason = enum has no representation hint
244 lint_improper_ctypes_enum_repr_help =
245 consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
247 lint_improper_ctypes_struct_fieldless_reason = this struct has no fields
248 lint_improper_ctypes_struct_fieldless_help = consider adding a member to this struct
250 lint_improper_ctypes_union_fieldless_reason = this union has no fields
251 lint_improper_ctypes_union_fieldless_help = consider adding a member to this union
253 lint_improper_ctypes_struct_non_exhaustive = this struct is non-exhaustive
254 lint_improper_ctypes_union_non_exhaustive = this union is non-exhaustive
256 lint_improper_ctypes_struct_layout_reason = this struct has unspecified layout
257 lint_improper_ctypes_struct_layout_help = consider adding a `#[repr(C)]` or `#[repr(transparent)]` attribute to this struct
259 lint_improper_ctypes_union_layout_reason = this union has unspecified layout
260 lint_improper_ctypes_union_layout_help = consider adding a `#[repr(C)]` or `#[repr(transparent)]` attribute to this union
262 lint_improper_ctypes_box = box cannot be represented as a single pointer
264 lint_improper_ctypes_enum_phantomdata = this enum contains a PhantomData field
266 lint_improper_ctypes_struct_zst = this struct contains only zero-sized fields
268 lint_improper_ctypes_array_reason = passing raw arrays by value is not FFI-safe
269 lint_improper_ctypes_array_help = consider passing a pointer to the array
271 lint_improper_ctypes_only_phantomdata = composed only of `PhantomData`
273 lint_variant_size_differences =
274 enum variant is more than three times larger ({$largest} bytes) than the next largest
276 lint_atomic_ordering_load = atomic loads cannot have `Release` or `AcqRel` ordering
277 .help = consider using ordering modes `Acquire`, `SeqCst` or `Relaxed`
279 lint_atomic_ordering_store = atomic stores cannot have `Acquire` or `AcqRel` ordering
280 .help = consider using ordering modes `Release`, `SeqCst` or `Relaxed`
282 lint_atomic_ordering_fence = memory fences cannot have `Relaxed` ordering
283 .help = consider using ordering modes `Acquire`, `Release`, `AcqRel` or `SeqCst`
285 lint_atomic_ordering_invalid = `{$method}`'s failure ordering may not be `Release` or `AcqRel`, since a failed `{$method}` does not result in a write
286 .label = invalid failure ordering
287 .help = consider using `Acquire` or `Relaxed` failure ordering instead
289 lint_unused_op = unused {$op} that must be used
290 .label = the {$op} produces a value
291 .suggestion = use `let _ = ...` to ignore the resulting value
293 lint_unused_result = unused result of type `{$ty}`
295 lint_unused_closure =
296 unused {$pre}{$count ->
299 }{$post} that must be used
300 .note = closures are lazy and do nothing unless called
302 lint_unused_generator =
303 unused {$pre}{$count ->
306 }{$post} that must be used
307 .note = generators are lazy and do nothing unless resumed
309 lint_unused_def = unused {$pre}`{$def}`{$post} that must be used
311 lint_path_statement_drop = path statement drops value
312 .suggestion = use `drop` to clarify the intent
314 lint_path_statement_no_effect = path statement with no effect
316 lint_unused_delim = unnecessary {$delim} around {$item}
317 .suggestion = remove these {$delim}
319 lint_unused_import_braces = braces around {$node} is unnecessary
321 lint_unused_allocation = unnecessary allocation, use `&` instead
322 lint_unused_allocation_mut = unnecessary allocation, use `&mut` instead
324 lint_builtin_while_true = denote infinite loops with `loop {"{"} ... {"}"}`
325 .suggestion = use `loop`
327 lint_builtin_box_pointers = type uses owned (Box type) pointers: {$ty}
329 lint_builtin_non_shorthand_field_patterns = the `{$ident}:` in this pattern is redundant
330 .suggestion = use shorthand field pattern
332 lint_builtin_overridden_symbol_name =
333 the linker's behavior with multiple libraries exporting duplicate symbol names is undefined and Rust cannot provide guarantees when you manually override them
335 lint_builtin_overridden_symbol_section =
336 the program's behavior with overridden link sections on items is unpredictable and Rust cannot provide guarantees when you manually override them
338 lint_builtin_allow_internal_unsafe =
339 `allow_internal_unsafe` allows defining macros using unsafe without triggering the `unsafe_code` lint at their call site
341 lint_builtin_unsafe_block = usage of an `unsafe` block
343 lint_builtin_unsafe_trait = declaration of an `unsafe` trait
345 lint_builtin_unsafe_impl = implementation of an `unsafe` trait
347 lint_builtin_no_mangle_fn = declaration of a `no_mangle` function
348 lint_builtin_export_name_fn = declaration of a function with `export_name`
349 lint_builtin_link_section_fn = declaration of a function with `link_section`
351 lint_builtin_no_mangle_static = declaration of a `no_mangle` static
352 lint_builtin_export_name_static = declaration of a static with `export_name`
353 lint_builtin_link_section_static = declaration of a static with `link_section`
355 lint_builtin_no_mangle_method = declaration of a `no_mangle` method
356 lint_builtin_export_name_method = declaration of a method with `export_name`
358 lint_builtin_decl_unsafe_fn = declaration of an `unsafe` function
359 lint_builtin_decl_unsafe_method = declaration of an `unsafe` method
360 lint_builtin_impl_unsafe_method = implementation of an `unsafe` method
362 lint_builtin_missing_doc = missing documentation for {$article} {$desc}
364 lint_builtin_missing_copy_impl = type could implement `Copy`; consider adding `impl Copy`
366 lint_builtin_missing_debug_impl =
367 type does not implement `{$debug}`; consider adding `#[derive(Debug)]` or a manual implementation
369 lint_builtin_anonymous_params = anonymous parameters are deprecated and will be removed in the next edition
370 .suggestion = try naming the parameter or explicitly ignoring it
372 lint_builtin_deprecated_attr_link = use of deprecated attribute `{$name}`: {$reason}. See {$link}
373 .msg_suggestion = {$msg}
374 .default_suggestion = remove this attribute
375 lint_builtin_deprecated_attr_used = use of deprecated attribute `{$name}`: no longer used.
376 lint_builtin_deprecated_attr_default_suggestion = remove this attribute
378 lint_builtin_unused_doc_comment = unused doc comment
379 .label = rustdoc does not generate documentation for {$kind}
380 .plain_help = use `//` for a plain comment
381 .block_help = use `/* */` for a plain comment
383 lint_builtin_no_mangle_generic = functions generic over types or consts must be mangled
384 .suggestion = remove this attribute
386 lint_builtin_const_no_mangle = const items should never be `#[no_mangle]`
387 .suggestion = try a static value
389 lint_builtin_mutable_transmutes =
390 transmuting &T to &mut T is undefined behavior, even if the reference is unused, consider instead using an UnsafeCell
392 lint_builtin_unstable_features = unstable feature
394 lint_ungated_async_fn_track_caller = `#[track_caller]` on async functions is a no-op
395 .label = this function will not propagate the caller location
397 lint_builtin_unreachable_pub = unreachable `pub` {$what}
398 .suggestion = consider restricting its visibility
399 .help = or consider exporting it for use by other crates
401 lint_builtin_unexpected_cli_config_name = unexpected `{$name}` as condition name
402 .help = was set with `--cfg` but isn't in the `--check-cfg` expected names
404 lint_builtin_unexpected_cli_config_value = unexpected condition value `{$value}` for condition name `{$name}`
405 .help = was set with `--cfg` but isn't in the `--check-cfg` expected values
407 lint_builtin_type_alias_bounds_help = use fully disambiguated paths (i.e., `<T as Trait>::Assoc`) to refer to associated types in type aliases
409 lint_builtin_type_alias_where_clause = where clauses are not enforced in type aliases
410 .suggestion = the clause will not be checked when the type alias is used, and should be removed
412 lint_builtin_type_alias_generic_bounds = bounds on generic parameters are not enforced in type aliases
413 .suggestion = the bound will not be checked when the type alias is used, and should be removed
415 lint_builtin_trivial_bounds = {$predicate_kind_name} bound {$predicate} does not depend on any type or lifetime parameters
417 lint_builtin_ellipsis_inclusive_range_patterns = `...` range patterns are deprecated
418 .suggestion = use `..=` for an inclusive range
420 lint_builtin_unnameable_test_items = cannot test inner items
422 lint_builtin_keyword_idents = `{$kw}` is a keyword in the {$next} edition
423 .suggestion = you can use a raw identifier to stay compatible
425 lint_builtin_explicit_outlives = outlives requirements can be inferred
426 .suggestion = remove {$count ->
428 *[other] these bounds
431 lint_builtin_incomplete_features = the feature `{$name}` is incomplete and may not be safe to use and/or cause compiler crashes
432 .note = see issue #{$n} <https://github.com/rust-lang/rust/issues/{$n}> for more information
433 .help = consider using `min_{$name}` instead, which is more stable and complete
435 lint_builtin_unpermitted_type_init_zeroed = the type `{$ty}` does not permit zero-initialization
436 lint_builtin_unpermitted_type_init_unint = the type `{$ty}` does not permit being left uninitialized
438 lint_builtin_unpermitted_type_init_label = this code causes undefined behavior when executed
439 lint_builtin_unpermitted_type_init_label_suggestion = help: use `MaybeUninit<T>` instead, and only call `assume_init` after initialization is done
441 lint_builtin_clashing_extern_same_name = `{$this}` redeclared with a different signature
442 .previous_decl_label = `{$orig}` previously declared here
443 .mismatch_label = this signature doesn't match the previous declaration
444 lint_builtin_clashing_extern_diff_name = `{$this}` redeclares `{$orig}` with a different signature
445 .previous_decl_label = `{$orig}` previously declared here
446 .mismatch_label = this signature doesn't match the previous declaration
448 lint_builtin_deref_nullptr = dereferencing a null pointer
449 .label = this code causes undefined behavior when executed
451 lint_builtin_asm_labels = avoid using named labels in inline assembly
453 lint_builtin_special_module_name_used_lib = found module declaration for lib.rs
454 .note = lib.rs is the root of this crate's library target
455 .help = to refer to it from other targets, use the library's name as the path
457 lint_builtin_special_module_name_used_main = found module declaration for main.rs
458 .note = a binary crate cannot be used as library
460 lint_supertrait_as_deref_target = `{$t}` implements `Deref` with supertrait `{$target_principal}` as target
461 .label = target type is set here
463 lint_overruled_attribute = {$lint_level}({$lint_source}) incompatible with previous forbid
464 .label = overruled by previous forbid
466 lint_default_source = `forbid` lint level is the default for {$id}
468 lint_node_source = `forbid` level set here
471 lint_command_line_source = `forbid` lint level was set on command line
473 lint_malformed_attribute = malformed lint attribute input
475 lint_bad_attribute_argument = bad attribute argument
477 lint_reason_must_be_string_literal = reason must be a string literal
479 lint_reason_must_come_last = reason in lint attribute must come last
481 lint_unknown_tool_in_scoped_lint = unknown tool name `{$tool_name}` found in scoped lint: `{$tool_name}::{$lint_name}`
482 .help = add `#![register_tool({$tool_name})]` to the crate root
484 lint_unsupported_group = `{$lint_group}` lint group is not supported with ´--force-warn´
486 lint_requested_level = requested on the command line with `{$level} {$lint_name}`
488 lint_check_name_unknown = unknown lint: `{$lint_name}`
489 .help = did you mean: `{$suggestion}`
491 lint_check_name_unknown_tool = unknown lint tool: `{$tool_name}`
493 lint_check_name_warning = {$msg}
495 lint_check_name_deprecated = lint name `{$lint_name}` is deprecated and does not have an effect anymore. Use: {$new_name}
497 lint_opaque_hidden_inferred_bound = opaque type `{$ty}` does not satisfy its associated type bounds
498 .specifically = this associated type bound is unsatisfied for `{$proj_ty}`
500 lint_opaque_hidden_inferred_bound_sugg = add this bound