ty::pretty: prevent infinite recursion for extern crate paths. #89738
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| r? @nagisa (rust-highfive has picked a reviewer for you, use r? to override) |
rust-highfive added the S-waiting-on-review 
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| cc @nikomatsakis @petrochenkov (I'm not sure who should review) |
nagisa reviewed Oct 10, 2021
| // in cases where the `extern crate foo` has non-trivial | ||
| // parents, e.g. it's nested in `impl foo::Trait for Bar` | ||
| // (see also issues #55779 and #87932). | ||
| self = with_no_visible_paths(|| self.print_def_path(def_id, &[]))?; |
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Reassigning self like this seems somewhat footgunny but looks like its already being done elsewhere…
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This mess of an API is all "linear" so there's not really any risk - the result has to be used, because a Self value has to be returned, and the call consumes self.
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| Seems reasonable enough to me. r=me, but giving some time for others to give a look too. |
apiraino added the T-compiler Member
| @bors r+ |
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| 📌 Commit f14e8dd has been approved by |
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bors added a commit to rust-lang-ci/rust that referenced this pull request Oct 17, 2021
…askrgr Rollup of 7 pull requests Successful merges: - rust-lang#89738 (ty::pretty: prevent infinite recursion for `extern crate` paths.) - rust-lang#89888 (Make `llvm.download-ci-llvm="if-available"` work for tier 2 targets with host tools) - rust-lang#89945 (Remove a mention to `copy_from_slice` from `clone_from_slice` doc) - rust-lang#89946 (Fix an ICE with TAITs and Future) - rust-lang#89963 (Some "parenthesis" and "parentheses" fixes) - rust-lang#89975 (Add a regression test for rust-lang#85921) - rust-lang#89977 (Make Result::as_mut const) Failed merges: r? `@ghost` `@rustbot` modify labels: rollup
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Fixes #55779, fixes #87932.
This fix is based on @estebank's idea in #55779 (comment) - but instead of trying to get
try_print_visible_def_path_recur's cycle detection to work in this case, this PR "just" disables the "visible path" feature when printing the path to anextern crate, so that the old recursion chain oftry_print_visible_def_path -> print_def_path -> try_print_visible_def_path, is now impossible.Both tests have been confirmed to crash
rustcbecause of a stack overflow, without the fix.