What is this issue?
If you're a crate author who's been linked here, your crate (indirectly) depends on a version of a procedural macro crate that will stop compiling in the future. All affected crates have updated versions published, so you should update to the latest version of the crate mentioned by the compiler warning you saw.
Background
In the past, the Rust compiler has had several bugs in the way that it passes a TokenStream to procedural macros ('proc-macro's). Fixing these bugs resulted in changes the input TokenStream, which some proc-macros were not prepared to handle.
To avoid breaking large portions of the ecosystem, several hardcoded hacks were added to the compiler. When specific macros from certain crates (e.g. time-macros-impl) are invoked, we invoke the macro with a modified TokenStream (what would have been used before the bugfix), which keeps the project compiling.
However, hard-coding specific crate and macro names in the compiler is a huge hack, which we'd like to remove as soon as possible. This issue tracks our progress towards removing all of these hacks.
About tracking issues
Tracking issues are used to record the overall progress of implementation.
They are also used as hubs connecting to other relevant issues, e.g., bugs or open design questions.
A tracking issue is however not meant for large scale discussion, questions, or bug reports about a feature.
Instead, open a dedicated issue for the specific matter and add the relevant feature gate label.
Steps
TODO
Unresolved Questions
Implementation history
What is this issue?
If you're a crate author who's been linked here, your crate (indirectly) depends on a version of a procedural macro crate that will stop compiling in the future. All affected crates have updated versions published, so you should update to the latest version of the crate mentioned by the compiler warning you saw.
Background
In the past, the Rust compiler has had several bugs in the way that it passes a
TokenStreamto procedural macros ('proc-macro's). Fixing these bugs resulted in changes the inputTokenStream, which some proc-macros were not prepared to handle.To avoid breaking large portions of the ecosystem, several hardcoded hacks were added to the compiler. When specific macros from certain crates (e.g.
time-macros-impl) are invoked, we invoke the macro with a modifiedTokenStream(what would have been used before the bugfix), which keeps the project compiling.However, hard-coding specific crate and macro names in the compiler is a huge hack, which we'd like to remove as soon as possible. This issue tracks our progress towards removing all of these hacks.
About tracking issues
Tracking issues are used to record the overall progress of implementation.
They are also used as hubs connecting to other relevant issues, e.g., bugs or open design questions.
A tracking issue is however not meant for large scale discussion, questions, or bug reports about a feature.
Instead, open a dedicated issue for the specific matter and add the relevant feature gate label.
Steps
TODO
Unresolved Questions
Implementation history