Detect missing `derive` on unresolved attribute even when not imported #142487

estebank · 2025-06-14T05:34:47Z

When encountering unresolved attributes, ensure the proc-macros for every crate in scope are added to the macro_map so that typos and missing derives are properly detected.

error: cannot find attribute `sede` in this scope
  --> $DIR/missing-derive-3.rs:20:7
   |
LL |     #[sede(untagged)]
   |       ^^^^
   |
help: the derive macros `Deserialize` and `Serialize` accept the similarly named `serde` attribute
   |
LL |     #[serde(untagged)]
   |         +

error: cannot find attribute `serde` in this scope
  --> $DIR/missing-derive-3.rs:14:7
   |
LL |     #[serde(untagged)]
   |       ^^^^^
   |
note: `serde` is imported here, but it is a crate, not an attribute
  --> $DIR/missing-derive-3.rs:4:1
   |
LL | extern crate serde;
   | ^^^^^^^^^^^^^^^^^^^
help: `serde` is an attribute that can be used by the derive macros `Deserialize` and `Serialize`, you might be missing a `derive` attribute
   |
LL + #[derive(Deserialize, Serialize)]
LL | enum B {
   |

Follow up to #134841. Fix #47608.

rustbot · 2025-06-14T05:34:52Z

r? @jieyouxu

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compiler/rustc_resolve/src/build_reduced_graph.rs

jieyouxu · 2025-06-14T10:25:12Z

r? compiler

compiler-errors · 2025-07-16T19:45:40Z

This needs a perf run firstly I think

@bors try parent=855e0fe46e68d94e9f6147531b75ac2d488c548e @rust-timer queue

compiler-errors · 2025-07-16T19:46:16Z

ugh, that will fail because bors1 doesn't know parents. I meant:

@bors2 try parent=855e0fe46e68d94e9f6147531b75ac2d488c548e @rust-timer queue

Detect missing `derive` on unresolved attribute even when not imported When encountering unresolved attributes, ensure the proc-macros for every crate in scope are added to the `macro_map` so that typos and missing `derive`s are properly detected. ``` error: cannot find attribute `sede` in this scope --> $DIR/missing-derive-3.rs:20:7 | LL | #[sede(untagged)] | ^^^^ | help: the derive macros `Deserialize` and `Serialize` accept the similarly named `serde` attribute | LL | #[serde(untagged)] | + error: cannot find attribute `serde` in this scope --> $DIR/missing-derive-3.rs:14:7 | LL | #[serde(untagged)] | ^^^^^ | note: `serde` is imported here, but it is a crate, not an attribute --> $DIR/missing-derive-3.rs:4:1 | LL | extern crate serde; | ^^^^^^^^^^^^^^^^^^^ help: `serde` is an attribute that can be used by the derive macros `Deserialize` and `Serialize`, you might be missing a `derive` attribute | LL + #[derive(Deserialize, Serialize)] LL | enum B { | ``` Follow up to #134841.

rust-bors · 2025-07-16T19:46:20Z

⌛ Trying commit d617a5b with merge 07b2f21…

To cancel the try build, run the command @bors2 try cancel.

rust-bors · 2025-07-16T22:00:56Z

☀️ Try build successful (CI)
Build commit: 07b2f21 (07b2f218801fa85db469fc131c97d08b0a40e9b9, parent: 855e0fe46e68d94e9f6147531b75ac2d488c548e)

rust-timer · 2025-07-16T23:10:38Z

Finished benchmarking commit (07b2f21): comparison URL.

Overall result: ❌ regressions - no action needed

Benchmarking this pull request means it may be perf-sensitive – we'll automatically label it not fit for rolling up. You can override this, but we strongly advise not to, due to possible changes in compiler perf.

@bors rollup=never
@rustbot label: -S-waiting-on-perf -perf-regression

Instruction count

Our most reliable metric. Used to determine the overall result above. However, even this metric can be noisy.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	0.4%	[0.4%, 0.5%]	3
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Max RSS (memory usage)

Results (secondary -1.9%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	2.3%	[2.3%, 2.3%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-6.2%	[-6.2%, -6.2%]	1
All ❌✅ (primary)	-	-	0

Cycles

Results (primary 2.3%, secondary -0.7%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	2.3%	[2.1%, 2.4%]	2
Regressions ❌ (secondary)	2.3%	[2.3%, 2.3%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-3.8%	[-3.8%, -3.8%]	1
All ❌✅ (primary)	2.3%	[2.1%, 2.4%]	2

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 464.604s -> 465.331s (0.16%)
Artifact size: 374.58 MiB -> 374.59 MiB (0.00%)

compiler-errors · 2025-08-14T17:02:47Z

r? petrochenkov maybe?

compiler/rustc_metadata/src/rmeta/decoder.rs

compiler/rustc_metadata/src/creader.rs

compiler/rustc_resolve/src/build_reduced_graph.rs

compiler/rustc_resolve/src/lib.rs

``` error: cannot find attribute `sede` in this scope --> $DIR/missing-derive-3.rs:20:7 | LL | #[sede(untagged)] | ^^^^ | help: the derive macros `Deserialize` and `Serialize` accept the similarly named `serde` attribute | LL | #[serde(untagged)] | + error: cannot find attribute `serde` in this scope --> $DIR/missing-derive-3.rs:14:7 | LL | #[serde(untagged)] | ^^^^^ | note: `serde` is imported here, but it is a crate, not an attribute --> $DIR/missing-derive-3.rs:4:1 | LL | extern crate serde; | ^^^^^^^^^^^^^^^^^^^ help: `serde` is an attribute that can be used by the derive macros `Deserialize` and `Serialize`, you might be missing a `derive` attribute | LL + #[derive(Deserialize, Serialize)] LL | enum B { | ```

estebank · 2025-08-15T16:04:12Z

Addressed and squashed.

petrochenkov · 2025-08-16T14:09:35Z

@bors r+

bors · 2025-08-16T14:09:38Z

📌 Commit 8baab4c has been approved by petrochenkov

It is now in the queue for this repository.

petrochenkov · 2025-08-16T14:10:47Z

compiler/rustc_metadata/src/rmeta/decoder.rs

+            for def_id in self.root.proc_macro_data.as_ref().into_iter().flat_map(move |data| {
+                data.macros
+                    .decode(CrateMetadataRef { cdata: self, cstore })
+                    .map(move |index| DefId { index, krate })


That said, in gen blocks you can use just fors and ifs with zero closures and iterator adapters.

bors · 2025-08-16T16:42:27Z

⌛ Testing commit 8baab4c with merge 69274a4...

Detect missing `derive` on unresolved attribute even when not imported When encountering unresolved attributes, ensure the proc-macros for every crate in scope are added to the `macro_map` so that typos and missing `derive`s are properly detected. ``` error: cannot find attribute `sede` in this scope --> $DIR/missing-derive-3.rs:20:7 | LL | #[sede(untagged)] | ^^^^ | help: the derive macros `Deserialize` and `Serialize` accept the similarly named `serde` attribute | LL | #[serde(untagged)] | + error: cannot find attribute `serde` in this scope --> $DIR/missing-derive-3.rs:14:7 | LL | #[serde(untagged)] | ^^^^^ | note: `serde` is imported here, but it is a crate, not an attribute --> $DIR/missing-derive-3.rs:4:1 | LL | extern crate serde; | ^^^^^^^^^^^^^^^^^^^ help: `serde` is an attribute that can be used by the derive macros `Deserialize` and `Serialize`, you might be missing a `derive` attribute | LL + #[derive(Deserialize, Serialize)] LL | enum B { | ``` Follow up to #134841. Fix #47608.

joshtriplett · 2025-08-16T21:55:55Z

compiler/rustc_resolve/src/build_reduced_graph.rs

@@ -210,6 +210,17 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
        }
    }

+    /// Add every proc macro accessible from the current crate to the `macro_map` so diagnostics can
+    /// find them for suggestions.
+    pub(crate) fn register_macros_for_all_crates(&mut self) {


The code this is replacing would register any non-proc-macro derives or attributes, if any; this seems to only register proc macros. With the addition of attr and derive rules for macro_rules! macros, this should be registering non-proc-macros for possible suggestions too.

bors · 2025-08-16T22:42:28Z

💥 Test timed out

rust-log-analyzer · 2025-08-16T22:44:35Z

A job failed! Check out the build log: (web) (plain enhanced) (plain)

Click to see the possible cause of the failure (guessed by this bot)

petrochenkov · 2025-08-18T16:15:28Z

@bors retry

rustbot assigned jieyouxu Jun 14, 2025

rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels Jun 14, 2025

estebank commented Jun 14, 2025

View reviewed changes

compiler/rustc_resolve/src/build_reduced_graph.rs Outdated Show resolved Hide resolved