mold 2.38.0 is a new release of the high-speed linker. It includes the following new features and bug fixes.
New Features
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The
--auditand--depauditoptions are now supported for compatibility with GNU ld. (af396ad) -
Recent versions of LLVM support an alternative, experimental relocation table format called CREL. mold can now read object files containing CREL relocation tables. (c43a859)
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[ARM32][ARM64][PPC32][PPC64] The branch instruction ranges of RISC processors are generally insufficient to support the medium code model because their instructions are typically 32 bits long, which makes it impossible to embed large immediate offsets. For example, ARM64’s branch instruction can target only PC ± 128 MiB. If the branch target is farther than that, the linker must emit a small piece of code—often called a thunk or branch island—to extend the branch range.
Previously, mold created unnecessary range extension thunks for symbols that had PLT entries. Now, mold does not create thunks unless they are truly needed. (a43f395)
Bug Fixes and Compatibility Improvements
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Previously,
--no-allow-shlib-undefinedcould cause a segmentation fault due to an out-of-bounds array access. This has been fixed. (82affb9) -
--no-allow-shlib-undefinedis enabled by default if the output type is an executable (as opposed to a shared library) for compatibility with other linkers. (43810df) -
mold could report a spurious "duplicate symbol" error when performing LTO. This bug has been fixed. (5d24db5)
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In rare cases involving symbol versioning, mold mistakenly filtered out necessary libraries specified with
--as-needed. This bug has been fixed. (a97a628) -
In rare cases involving symbol versioning, mold reported a spurious "undefined symbol" error. This bug has been fixed. (2d6061a)
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If the same symbol was defined with and without the default version (e.g., if an object file defined both
fooandfoo@@VERSION), mold mistakenly hid both symbols from the dynamic symbol table instead of exporting the default one (e.g.,foo@@VERSION). This bug has been fixed. (ac6f1ec)
Acknowledgements
mold is an open-source project, and we accept donations via GitHub Sponsors and OpenCollective. We thank everyone who sponsors our project. In particular, we would like to acknowledge the following organizations and people who have sponsored $32/month or more during this release cycle: