Expand diagnostic for attributes on macro calls#158106
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| #[derive(Subdiagnostic)] | ||
| pub(crate) enum OnMacroCall { | ||
| #[warning("this representation attribute is ignored")] |
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Why is the repr attribute special cased?
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It's a particular dangerous mistake because people assume that it acts on the macro expension. It is one of those things where you think you know what it does but are wrong.
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Hmmm I'm not sure I really like that special case, I think the extra warning message is not really helping the user understand it better, the note you added should be enough
| pub(crate) enum OnMacroCall { | ||
| #[warning("this representation attribute is ignored")] | ||
| #[note( | ||
| "attributes on macro invocations do nothing even if the macro expands to what would be a valid target for the attribute" |
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This is not true, the cfg and cfg_attr attribute do work, and I'm expecting proc macro attributes to also work but not sure.
Maybe change it to
"this attribute does nothing on macro invocations..."
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Right, I forgot about the active attributes.
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Reminder, once the PR becomes ready for a review, use |
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@bors r+ rollup |
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Expand diagnostic for attributes on macro calls As far as I am aware there are no attributes that do something when used on macro invocations. r? @JonathanBrouwer
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As far as I am aware there are no attributes that do something when used on macro invocations.
r? @JonathanBrouwer