diff options
Diffstat (limited to 'compiler/rustc_error_codes/src/error_codes/E0773.md')
-rw-r--r-- | compiler/rustc_error_codes/src/error_codes/E0773.md | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/compiler/rustc_error_codes/src/error_codes/E0773.md b/compiler/rustc_error_codes/src/error_codes/E0773.md new file mode 100644 index 000000000..b19a58bf3 --- /dev/null +++ b/compiler/rustc_error_codes/src/error_codes/E0773.md @@ -0,0 +1,38 @@ +A builtin-macro was defined more than once. + +Erroneous code example: + +```compile_fail,E0773 +#![feature(decl_macro)] +#![feature(rustc_attrs)] + +#[rustc_builtin_macro] +pub macro test($item:item) { + /* compiler built-in */ +} + +mod inner { + #[rustc_builtin_macro] + pub macro test($item:item) { + /* compiler built-in */ + } +} +``` + +To fix the issue, remove the duplicate declaration: + +``` +#![feature(decl_macro)] +#![feature(rustc_attrs)] + +#[rustc_builtin_macro] +pub macro test($item:item) { + /* compiler built-in */ +} +``` + +In very rare edge cases, this may happen when loading `core` or `std` twice, +once with `check` metadata and once with `build` metadata. +For more information, see [#75176]. + +[#75176]: https://github.com/rust-lang/rust/pull/75176#issuecomment-683234468 |