Add -Zinstrument-mcount={fentry-nop-record,fentry-record} - #160184
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| match opts.unstable_opts.instrument_mcount { | ||
| InstrumentMcount::Mcount(_) => { | ||
| fp.ratchet(FramePointer::Always); | ||
| } | ||
| _ => {} |
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You can avoid turning it into match with this:
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| match opts.unstable_opts.instrument_mcount { | |
| InstrumentMcount::Mcount(_) => { | |
| fp.ratchet(FramePointer::Always); | |
| } | |
| _ => {} | |
| if let InstrumentMcount::Mcount(_) = opts.unstable_opts.instrument_mcount { | |
| fp.ratchet(FramePointer::Always); | |
| } |
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| o => { | ||
| panic!("Unsupported or impossible mcount option {o:?}"); | ||
| } | ||
| InstrumentMcount::Disabled => {} |
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Reminder, once the PR becomes ready for a review, use |
The linux kernel still uses fentry for x86 and s390x arches. s390x depends entirely on the compiler to record and nop these sections. This facilitates support for inserting nop's and/or recording the location of each mcount call in a special section named `__mcount_loc`. These attributes are currently only supported with fentry on the s390x target, otherwise they are quietly ignored (except on s390x).
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Sorry, the update has slipped under my radar.
@bors r+
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Add -Zinstrument-mcount={fentry-nop-record,fentry-record}
The linux kernel still uses fentry for x86 and s390x arches. s390x depends entirely on the compiler to record and nop these sections.
This facilitates support for inserting nop's and/or recording the location of each mcount call in a special section named `__mcount_loc`.
These attributes are currently only supported with fentry on the s390x target, otherwise they are quietly ignored (except on s390x).
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…uwer Rollup of 23 pull requests Successful merges: - #153749 (Account for ownership mismatch on argument that doesn't meet bound) - #159326 (Deny multiple EII impls on a single item) - #159535 (Optimize slice::contains for bytewise types) - #159595 (Promote loongarch32-unknown-none* to Tier 2) - #160007 (allow `-Ldependency` search paths for panic runtimes) - #160184 (Add -Zinstrument-mcount={fentry-nop-record,fentry-record}) - #160320 (point at trait definition when it is used as a derive macro) - #160369 (When suggesting method names, prefer *exact* doc aliases over similar names) - #160406 (`DepKind` cleanups) - #160424 (Use `thread::available_parallelism` as the default limit for backend parallelism) - #159303 (Fix ICE for direct inline const generic defaults) - #159977 (Add regression test for bool indexing codegen) - #160011 (remove InterpError::map_err_info) - #160165 (reject `...` without pattern post-expansion) - #160295 (Fix rustdoc ICE when checking if a generic arg can be elided) - #160305 (Linkify C-SKY targets in `platform-support.md`) - #160314 (fix borrowck ICE for consts with fn pointer type) - #160322 (ElaborateBoxDeref: remove unnecessary projection) - #160338 (Add regression test for supertrait associated type normalization through dyn) - #160340 (Add regression test for unused_parens on contract clauses) - #160371 (Add doc aliases for transpositions `read_exact_buf` and `read_exact_buf_at`) - #160384 (Add PR body notes for Cargo lock file maintenance) - #160435 (bump tracing-tree)
JonathanBrouwer
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Add -Zinstrument-mcount={fentry-nop-record,fentry-record}
The linux kernel still uses fentry for x86 and s390x arches. s390x depends entirely on the compiler to record and nop these sections.
This facilitates support for inserting nop's and/or recording the location of each mcount call in a special section named `__mcount_loc`.
These attributes are currently only supported with fentry on the s390x target, otherwise they are quietly ignored (except on s390x).
rust-bors Bot
pushed a commit
that referenced
this pull request
Aug 4, 2026
…uwer Rollup of 26 pull requests Successful merges: - #153749 (Account for ownership mismatch on argument that doesn't meet bound) - #158727 (std: use `readdir` on nearly all UNIX platforms) - #159130 (a bit optimize four-digit chunks in integer formatting) - #159326 (Deny multiple EII impls on a single item) - #159535 (Optimize slice::contains for bytewise types) - #159595 (Promote loongarch32-unknown-none* to Tier 2) - #160184 (Add -Zinstrument-mcount={fentry-nop-record,fentry-record}) - #160320 (point at trait definition when it is used as a derive macro) - #160369 (When suggesting method names, prefer *exact* doc aliases over similar names) - #160406 (`DepKind` cleanups) - #160424 (Use `thread::available_parallelism` as the default limit for backend parallelism) - #159303 (Fix ICE for direct inline const generic defaults) - #159977 (Add regression test for bool indexing codegen) - #160011 (remove InterpError::map_err_info) - #160165 (reject `...` without pattern post-expansion) - #160295 (Fix rustdoc ICE when checking if a generic arg can be elided) - #160305 (Linkify C-SKY targets in `platform-support.md`) - #160314 (fix borrowck ICE for consts with fn pointer type) - #160322 (ElaborateBoxDeref: remove unnecessary projection) - #160338 (Add regression test for supertrait associated type normalization through dyn) - #160340 (Add regression test for unused_parens on contract clauses) - #160371 (Add doc aliases for transpositions `read_exact_buf` and `read_exact_buf_at`) - #160384 (Add PR body notes for Cargo lock file maintenance) - #160412 (Move duplicate-names check for #[rustc_must_implement_one_of] to attribute parser) - #160435 (bump tracing-tree) - #160449 (Fix lookup of object files)
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The linux kernel still uses fentry for x86 and s390x arches. s390x depends entirely on the compiler to record and nop these sections.
This facilitates support for inserting nop's and/or recording the location of each mcount call in a special section named
__mcount_loc.These attributes are currently only supported with fentry on the s390x target, otherwise they are quietly ignored (except on s390x).