Filter Rust stdlib/dependency paths from profiling by default#275
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emeryberger merged 4 commits intomasterfrom Mar 3, 2026
Merged
Filter Rust stdlib/dependency paths from profiling by default#275emeryberger merged 4 commits intomasterfrom
emeryberger merged 4 commits intomasterfrom
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When profiling Rust programs, coz was attributing results to lines in
the Rust standard library and third-party dependencies because their
source paths (e.g. /rustc/<hash>/..., ~/.rustup/..., ~/.cargo/...)
were not recognized as system paths.
Changes:
- Extract path filtering functions into libcoz/path_filter.h for
reuse and testability
- Add is_rust_path() to identify Rust toolchain and dependency paths:
/rustc/... (always filtered), $HOME/.rustup/... and
$HOME/.cargo/{registry,git}/... (filtered using actual $HOME)
- Rust paths are filtered by default but an explicit --source-scope
overrides the filter
- Remove #[cfg(target_os = "linux")] gate from the Rust crate's
coz_get_counter — dlsym is POSIX-standard, so progress macros now
work on macOS too
- Add unit tests (65 assertions) and a Rust integration test that
verifies DWARF debug info contains /rustc/ paths and confirms
they are excluded from profiling output
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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…tform gates - Remove duplicate static is_coz_header() from inspect.cpp (already in path_filter.h) - Remove #[cfg(target_os = "linux")] gates re-added during merge to rust/src/lib.rs - Remove #[cfg(not(target_os = "linux"))] no-op stubs re-added during merge Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Summary
When profiling Rust programs, coz was attributing results to lines in the Rust standard library and third-party dependencies. Their source paths (
/rustc/<hash>/...,~/.rustup/...,~/.cargo/registry/...) were not recognized as system paths, so they passed through source filtering and appeared in profiling output.libcoz/path_filter.hfor reuse and testabilityis_rust_path()to identify Rust toolchain/dependency paths:/rustc/...— always filtered (synthetic paths embedded by rustc)$HOME/.rustup/...— filtered only when under the user's actual$HOME$HOME/.cargo/registry/...and$HOME/.cargo/git/...— same%source scope), but an explicit--source-scopeoverrides the filter#[cfg(target_os = "linux")]gate from the Rust crate'scoz_get_counterfunction —dlsymis POSIX-standard, socoz::progress!()and other macros now work on macOS too$HOMEscoping, scope override behavior/rustc/paths, and validates they are excluded from profiling outputSupersedes #272 and #274.
Test plan
tests/path_filter/path_filter_test.cpp)tests/run_rust_filter_test.sh)/rustc/paths in DWARF debug info--source-scope '/rustc/%'overrides the filter when explicitly requested🤖 Generated with Claude Code