Rollup merge of rust-lang#112708 - flip1995:clippy-freezing-pc-with-i…

…ce, r=cjgillot

Revert "Don't hold the active queries lock while calling `make_query`"

This reverts commit fd3d2d4.

This has the side effect, that when Clippy should ICE (during an EarlyPass?) it will fill up the RAM with 2 GB/s and then freezes the PC. I don't know the correct solution, but this is blocking the Clippy sync and might give some people really bad experiences, so this should be reverted ASAP.

Reverts rust-lang#112333

r? `@cjgillot`
cc `@Zoxc`

I only commented this on [Zulip](https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler/topic/.60try_print_query_stack.60.20has.20.60ImplicitCtx.60.20during.20.60EarlyPass.60/near/363926180). I should've left a comment on the PR as well. My bad.

compiler/rustc_query_system/src/query/plumbing.rs

@@ -69,8 +69,6 @@ where
         make_query: fn(Qcx, K) -> QueryStackFrame<D>,
         jobs: &mut QueryMap<D>,
     ) -> Option<()> {
-        let mut active = Vec::new();
-
         #[cfg(parallel_compiler)]
         {
             // We use try_lock_shards here since we are called from the
@@ -79,7 +77,8 @@ where
             for shard in shards.iter() {
                 for (k, v) in shard.iter() {
                     if let QueryResult::Started(ref job) = *v {
-                        active.push((*k, job.clone()));
+                        let query = make_query(qcx, *k);
+                        jobs.insert(job.id, QueryJobInfo { query, job: job.clone() });
                     }
                 }
             }
@@ -92,18 +91,12 @@ where
             // really hurt much.)
             for (k, v) in self.active.try_lock()?.iter() {
                 if let QueryResult::Started(ref job) = *v {
-                    active.push((*k, job.clone()));
+                    let query = make_query(qcx, *k);
+                    jobs.insert(job.id, QueryJobInfo { query, job: job.clone() });
                 }
             }
         }
 
-        // Call `make_query` while we're not holding a `self.active` lock as `make_query` may call
-        // queries leading to a deadlock.
-        for (key, job) in active {
-            let query = make_query(qcx, key);
-            jobs.insert(job.id, QueryJobInfo { query, job });
-        }
-
         Some(())
     }
 }

tests/ui/treat-err-as-bug/panic-causes-oom-112708.rs

@@ -0,0 +1,11 @@
+// compile-flags: -Ztreat-err-as-bug
+// dont-check-failure-status
+// error-pattern: aborting due to `-Z treat-err-as-bug=1`
+// normalize-stderr-test "note: .*\n\n" -> ""
+// normalize-stderr-test "thread 'rustc' panicked.*\n" -> ""
+// rustc-env:RUST_BACKTRACE=0
+
+fn main() {
+    #[deny(while_true)]
+    while true {}
+}

tests/ui/treat-err-as-bug/panic-causes-oom-112708.stderr

@@ -0,0 +1,16 @@
+error: denote infinite loops with `loop { ... }`
+  --> $DIR/panic-causes-oom-112708.rs:10:5
+   |
+LL |     while true {}
+   |     ^^^^^^^^^^ help: use `loop`
+   |
+note: the lint level is defined here
+  --> $DIR/panic-causes-oom-112708.rs:9:12
+   |
+LL |     #[deny(while_true)]
+   |            ^^^^^^^^^^
+
+error: the compiler unexpectedly panicked. this is a bug.
+
+query stack during panic:
+thread panicked while processing panic. aborting.