Fix ICE: attempted to remap an already remapped filename#138556

charmitro · 2025-03-16T10:30:01Z

This commit fixes an internal compiler error (ICE) that occurs when
rustdoc attempts to process macros with a remapped filename. The issue
arose during macro expansion when the --remap-path-prefix option was
used.

Instead of passing remapped filenames through, which would trigger the
"attempted to remap an already remapped filename" panic, we now
extract the original local path from remapped filenames before
processing them.

A test case has been added to verify this behavior.

Fixes #138520

rustbot · 2025-03-16T10:30:06Z

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compiler/rustc_span/src/source_map.rs

src/librustdoc/clean/render_macro_matchers.rs

nnethercote · 2025-03-16T20:15:16Z

Reassigning the review to @Urgau, who has stronger opinions and more expertise here than I do.

This commit fixes an internal compiler error (ICE) that occurs when rustdoc attempts to process macros with a remapped filename. The issue arose during macro expansion when the `--remap-path-prefix` option was used. Instead of passing remapped filenames through, which would trigger the "attempted to remap an already remapped filename" panic, we now extract the original local path from remapped filenames before processing them. A test case has been added to verify this behavior. Fixes rust-lang#138520 Signed-off-by: Charalampos Mitrodimas <charmitro@posteo.net>

GuillaumeGomez · 2025-03-17T13:16:13Z

Looks good to me, thanks for working on this! I'll let @Urgau have the final word.

Urgau · 2025-03-17T16:39:15Z

@bors r=GuillaumeGomez,Urgau rollup

bors · 2025-03-17T16:39:18Z

📌 Commit b148106 has been approved by GuillaumeGomez,Urgau

It is now in the queue for this repository.

…iaskrgr Rollup of 7 pull requests Successful merges: - rust-lang#138384 (Move `hir::Item::ident` into `hir::ItemKind`.) - rust-lang#138508 (Clarify "owned data" in E0515.md) - rust-lang#138531 (Store test diffs in job summaries and improve analysis formatting) - rust-lang#138533 (Only use `DIST_TRY_BUILD` for try jobs that were not selected explicitly) - rust-lang#138556 (Fix ICE: attempted to remap an already remapped filename) - rust-lang#138608 (rustc_target: Add target feature constraints for LoongArch) - rust-lang#138619 (Flatten `if`s in `rustc_codegen_ssa`) r? `@ghost` `@rustbot` modify labels: rollup

…e, r=GuillaumeGomez,Urgau Fix ICE: attempted to remap an already remapped filename This commit fixes an internal compiler error (ICE) that occurs when rustdoc attempts to process macros with a remapped filename. The issue arose during macro expansion when the `--remap-path-prefix` option was used. Instead of passing remapped filenames through, which would trigger the "attempted to remap an already remapped filename" panic, we now extract the original local path from remapped filenames before processing them. A test case has been added to verify this behavior. Fixes rust-lang#138520

Rollup of 7 pull requests Successful merges: - rust-lang#136320 (exit: document interaction with C) - rust-lang#138301 (Implement `read_buf` for Hermit) - rust-lang#138508 (Clarify "owned data" in E0515.md) - rust-lang#138556 (Fix ICE: attempted to remap an already remapped filename) - rust-lang#138569 (rustdoc-json: Add tests for `#[repr(...)]`) - rust-lang#138608 (rustc_target: Add target feature constraints for LoongArch) - rust-lang#138619 (Flatten `if`s in `rustc_codegen_ssa`) r? `@ghost` `@rustbot` modify labels: rollup

…iaskrgr Rollup of 7 pull requests Successful merges: - rust-lang#138384 (Move `hir::Item::ident` into `hir::ItemKind`.) - rust-lang#138508 (Clarify "owned data" in E0515.md) - rust-lang#138531 (Store test diffs in job summaries and improve analysis formatting) - rust-lang#138533 (Only use `DIST_TRY_BUILD` for try jobs that were not selected explicitly) - rust-lang#138556 (Fix ICE: attempted to remap an already remapped filename) - rust-lang#138608 (rustc_target: Add target feature constraints for LoongArch) - rust-lang#138619 (Flatten `if`s in `rustc_codegen_ssa`) r? `@ghost` `@rustbot` modify labels: rollup

Rollup merge of rust-lang#138556 - charmitro:already-remapped-filename, r=GuillaumeGomez,Urgau Fix ICE: attempted to remap an already remapped filename This commit fixes an internal compiler error (ICE) that occurs when rustdoc attempts to process macros with a remapped filename. The issue arose during macro expansion when the `--remap-path-prefix` option was used. Instead of passing remapped filenames through, which would trigger the "attempted to remap an already remapped filename" panic, we now extract the original local path from remapped filenames before processing them. A test case has been added to verify this behavior. Fixes rust-lang#138520

…iaskrgr Rollup of 7 pull requests Successful merges: - rust-lang#138384 (Move `hir::Item::ident` into `hir::ItemKind`.) - rust-lang#138508 (Clarify "owned data" in E0515.md) - rust-lang#138531 (Store test diffs in job summaries and improve analysis formatting) - rust-lang#138533 (Only use `DIST_TRY_BUILD` for try jobs that were not selected explicitly) - rust-lang#138556 (Fix ICE: attempted to remap an already remapped filename) - rust-lang#138608 (rustc_target: Add target feature constraints for LoongArch) - rust-lang#138619 (Flatten `if`s in `rustc_codegen_ssa`) r? `@ghost` `@rustbot` modify labels: rollup

With the minimum version bump in place, `rustdoc` now always recognizes the `--remap-path-prefix` flag. In addition, the Internal Compiler Error that the comment mentions [1] was fixed in Rust 1.87.0 [2], so we still need to skip the flag for the normal `rustdoc` case, but not for `--test` since the ICE does not reproduce there -- please see commit 2c8725c ("rust: kbuild: skip `--remap-path-prefix` for `rustdoc`"). Thus update the comment and remove the skipping of the flag for the `--test` case. Note that commit dda1350 ("rust: build: remap path to avoid absolute path") re-landed the `--remap-path-prefix` flag (together with `--remap-path-scope`), so we keep the workaround, i.e. an alternative could have been to simply delete the skip entirely, but since we still have it and it will be needed when this gets merged, let's keep it. Link: rust-lang/rust#138520 [1] Link: rust-lang/rust#138556 [2] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

The Internal Compiler Error that the comment mentions [1] was fixed in Rust 1.87.0 [2]. And, for other workarounds, we plan on limiting where we apply them [3]. Thus limit the ICE one too. This will help to make sure the workaround is not needed anymore on newer versions. Link: rust-lang/rust#138520 [1] Link: rust-lang/rust#138556 [2] Link: https://lore.kernel.org/rust-for-linux/20260205131815.2943152-2-mlksvender@gmail.com/ [3] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

With the minimum version bump in place, `rustdoc` now always recognizes the `--remap-path-prefix` flag. In addition, the Internal Compiler Error that the comment mentions [1] was fixed in Rust 1.87.0 [2], so we still need to skip the flag for the normal `rustdoc` case, but not for `--test` since the ICE does not reproduce there -- please see commit 2c8725c ("rust: kbuild: skip `--remap-path-prefix` for `rustdoc`"). Thus update the comment and remove the skipping of the flag for the `--test` case. Note that commit dda1350 ("rust: build: remap path to avoid absolute path") re-landed the `--remap-path-prefix` flag (together with `--remap-path-scope`), so we keep the workaround, i.e. an alternative could have been to simply delete the skip entirely, but since we still have it and it will be needed when this gets merged, let's keep it. Link: rust-lang/rust#138520 [1] Link: rust-lang/rust#138556 [2] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

The Internal Compiler Error that the comment mentions [1] was fixed in Rust 1.87.0 [2]. And, for other workarounds, we plan on limiting where we apply them [3]. Thus limit the ICE one too. This will help to make sure the workaround is not needed anymore on newer versions. Link: rust-lang/rust#138520 [1] Link: rust-lang/rust#138556 [2] Link: https://lore.kernel.org/rust-for-linux/20260205131815.2943152-2-mlksvender@gmail.com/ [3] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

With the minimum version bump in place, `rustdoc` now always recognizes the `--remap-path-prefix` flag. In addition, the Internal Compiler Error that the comment mentions [1] was fixed in Rust 1.87.0 [2], so we still need to skip the flag for the normal `rustdoc` case, but not for `--test` since the ICE does not reproduce there -- please see commit 2c8725c ("rust: kbuild: skip `--remap-path-prefix` for `rustdoc`"). Thus update the comment and remove the skipping of the flag for the `--test` case. Note that commit dda1350 ("rust: build: remap path to avoid absolute path") re-landed the `--remap-path-prefix` flag (together with `--remap-path-scope`), so we keep the workaround, i.e. an alternative could have been to simply delete the skip entirely, but since we still have it and it will be needed when this gets merged, let's keep it. Link: rust-lang/rust#138520 [1] Link: rust-lang/rust#138556 [2] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

The Internal Compiler Error that the comment mentions [1] was fixed in Rust 1.87.0 [2]. And, for other workarounds, we plan on limiting where we apply them [3]. Thus limit the ICE one too. This will help to make sure the workaround is not needed anymore on newer versions. Link: rust-lang/rust#138520 [1] Link: rust-lang/rust#138556 [2] Link: https://lore.kernel.org/rust-for-linux/20260205131815.2943152-2-mlksvender@gmail.com/ [3] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

With the minimum version bump in place, `rustdoc` now always recognizes the `--remap-path-prefix` flag. In addition, the Internal Compiler Error that the comment mentions [1] was fixed in Rust 1.87.0 [2], so we still need to skip the flag for the normal `rustdoc` case, but not for `--test` since the ICE does not reproduce there -- please see commit 2c8725c ("rust: kbuild: skip `--remap-path-prefix` for `rustdoc`"). Thus update the comment and remove the skipping of the flag for the `--test` case. Note that commit dda1350 ("rust: build: remap path to avoid absolute path") re-landed the `--remap-path-prefix` flag (together with `--remap-path-scope`), so we keep the workaround, i.e. an alternative could have been to simply delete the skip entirely, but since we still have it and it will be needed when this gets merged, let's keep it. Link: rust-lang/rust#138520 [1] Link: rust-lang/rust#138556 [2] Signed-off-by: Miguel Ojeda <ojeda@kernel.org> Link: https://lore.kernel.org/r/20260401114540.30108-9-ojeda@kernel.org Signed-off-by: Alice Ryhl <aliceryhl@google.com>

The Internal Compiler Error that the comment mentions [1] was fixed in Rust 1.87.0 [2]. And, for other workarounds, we plan on limiting where we apply them [3]. Thus limit the ICE one too. This will help to make sure the workaround is not needed anymore on newer versions. Link: rust-lang/rust#138520 [1] Link: rust-lang/rust#138556 [2] Link: https://lore.kernel.org/rust-for-linux/20260205131815.2943152-2-mlksvender@gmail.com/ [3] Signed-off-by: Miguel Ojeda <ojeda@kernel.org> Link: https://lore.kernel.org/r/20260401114540.30108-10-ojeda@kernel.org Signed-off-by: Alice Ryhl <aliceryhl@google.com>

Commit 8cf5b3f ("Revert "kbuild, rust: use -fremap-path-prefix to make paths relative"") removed `--remap-path-prefix` from the build system, so the workarounds are not needed anymore. Thus remove them. Note that the flag has landed again in parallel in this cycle in commit dda1350 ("rust: build: remap path to avoid absolute path"), together with `--remap-path-scope=macro` [1]. However, they are gated on `rustc-option-yn, --remap-path-scope=macro`, which means they are both only passed starting with Rust 1.95.0 [2]: `--remap-path-scope` is only stable in Rust 1.95, so use `rustc-option` to detect its presence. This feature has been available as `-Zremap-path-scope` for all versions that we support; however due to bugs in the Rust compiler, it does not work reliably until 1.94. I opted to not enable it for 1.94 as it's just a single version that we missed. In turn, that means the workarounds removed here should not be needed again (even with the flag added again above), since: - `rustdoc` now recognizes the `--remap-path-prefix` flag since Rust 1.81.0 [3] (even if it is still an unstable feature [4]). - The Internal Compiler Error [5] that the comment mentions was fixed in Rust 1.87.0 [6]. We tested that was the case in a previous version of this series by making the workaround conditional [7][8]. ...which are both older versions than Rust 1.95.0. We will still need to skip `--remap-path-scope` for `rustdoc` though, since `rustdoc` does not support that one yet [4]. Link: rust-lang/rust#111540 [1] Link: rust-lang/rust#147611 [2] Link: rust-lang/rust#107099 [3] Link: https://doc.rust-lang.org/nightly/rustdoc/unstable-features.html#--remap-path-prefix-remap-source-code-paths-in-output [4] Link: rust-lang/rust#138520 [5] Link: rust-lang/rust#138556 [6] Link: https://lore.kernel.org/rust-for-linux/20260401114540.30108-9-ojeda@kernel.org/ [7] Link: https://lore.kernel.org/rust-for-linux/20260401114540.30108-10-ojeda@kernel.org/ [8] Acked-by: Gary Guo <gary@garyguo.net> Link: https://patch.msgid.link/20260405235309.418950-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Commit 8cf5b3f ("Revert "kbuild, rust: use -fremap-path-prefix to make paths relative"") removed `--remap-path-prefix` from the build system, so the workarounds are not needed anymore. Thus remove them. Note that the flag has landed again in parallel in this cycle in commit dda1350 ("rust: build: remap path to avoid absolute path"), together with `--remap-path-scope=macro` [1]. However, they are gated on `rustc-option-yn, --remap-path-scope=macro`, which means they are both only passed starting with Rust 1.95.0 [2]: `--remap-path-scope` is only stable in Rust 1.95, so use `rustc-option` to detect its presence. This feature has been available as `-Zremap-path-scope` for all versions that we support; however due to bugs in the Rust compiler, it does not work reliably until 1.94. I opted to not enable it for 1.94 as it's just a single version that we missed. In turn, that means the workarounds removed here should not be needed again (even with the flag added again above), since: - `rustdoc` now recognizes the `--remap-path-prefix` flag since Rust 1.81.0 [3] (even if it is still an unstable feature [4]). - The Internal Compiler Error [5] that the comment mentions was fixed in Rust 1.87.0 [6]. We tested that was the case in a previous version of this series by making the workaround conditional [7][8]. ...which are both older versions than Rust 1.95.0. We will still need to skip `--remap-path-scope` for `rustdoc` though, since `rustdoc` does not support that one yet [4]. Link: rust-lang/rust#111540 [1] Link: rust-lang/rust#147611 [2] Link: rust-lang/rust#107099 [3] Link: https://doc.rust-lang.org/nightly/rustdoc/unstable-features.html#--remap-path-prefix-remap-source-code-paths-in-output [4] Link: rust-lang/rust#138520 [5] Link: rust-lang/rust#138556 [6] Link: https://lore.kernel.org/rust-for-linux/20260401114540.30108-9-ojeda@kernel.org/ [7] Link: https://lore.kernel.org/rust-for-linux/20260401114540.30108-10-ojeda@kernel.org/ [8] Link: https://patch.msgid.link/20260405235309.418950-2-ojeda@kernel.org Acked-by: Gary Guo <gary@garyguo.net> Reviewed-by: Tamir Duberstein <tamird@kernel.org> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

rustbot assigned nnethercote Mar 16, 2025

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matthiaskrgr mentioned this pull request Mar 17, 2025

Rollup of 7 pull requests #138630

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Rollup of 12 pull requests #138636

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jhpratt mentioned this pull request Mar 18, 2025

Rollup of 7 pull requests #138637

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bors merged commit cd4dfd7 into rust-lang:master Mar 18, 2025
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ojeda mentioned this pull request Mar 18, 2025

rustdoc wanted features & bugfixes Rust-for-Linux/linux#350

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winterqt mentioned this pull request May 9, 2025

ICE during stage2 lib rustdoc invocation when remapping build path prefix #140778

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Fix ICE: attempted to remap an already remapped filename#138556