fix(elf): detect imports via SHN_UNDEF instead of st_value (fixes #419)#534
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wyf027 wants to merge 2 commits into
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fix(elf): detect imports via SHN_UNDEF instead of st_value (fixes #419)#534wyf027 wants to merge 2 commits into
wyf027 wants to merge 2 commits into
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On MIPS, undefined dynamic symbols can have a non-zero st_value while still referencing SHN_UNDEF. Using st_shndx fixes false positives when filtering exported symbols (fixes m4b#419). Co-authored-by: Cursor <cursoragent@cursor.com>
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Resolved the rustfmt CI failure in commit 2b42a39 by applying the formatter to src/elf/sym.rs. Local verification: cargo fmt -- --check. |
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Summary
Sym::is_import()to treat symbols withst_shndx == SHN_UNDEFas imports instead of relying onst_value == 0.is_import()helper to takeshndxrather thanst_value.st_value.Fixes #419.
On MIPS ELF, undefined dynamic symbols (e.g.
memcpy@GLIBC_2.0) can have a non-zerost_valuewhile still being imports. The previous heuristic incorrectly classified them as defined exports.As suggested by @philipc in the issue, checking
st_shndx == SHN_UNDEFis the reliable indicator.Test plan
cargo test is_importcargo test --lib