1 =======================
2 LLD 7.0.0 Release Notes
3 =======================
11 lld is a high-performance linker that supports ELF (Unix), COFF (Windows),
12 Mach-O (macOS), MinGW and WebAssembly. lld is command-line-compatible with GNU
13 linkers and Microsoft link.exe, and is significantly faster than these system
16 lld 7 for ELF and COFF are production-ready. lld/ELF can build the entire
17 FreeBSD/AMD64 and will be the default linker of the next version of the
18 operating system. lld/COFF is being used to build popular large programs such as
19 the Chrome web browser. Mach-O, MinGW and WebAssembly supports are still
22 Non-comprehensive list of changes in this release
23 =================================================
28 * Fixed a lot of long-tail compatibility issues with GNU linkers.
30 * Added ``-z retpolineplt`` to emit a PLT entry that doesn't contain an indirect
31 jump instruction to mitigate Spectre v2 vulnerability.
33 * Added experimental support for `SHT_RELR sections
34 <https://groups.google.com/forum/#!topic/generic-abi/bX460iggiKg>`_ to create a
35 compact dynamic relocation table.
37 * Added support for `split stacks <https://gcc.gnu.org/wiki/SplitStacks>`_.
39 * Added support for address significance table (section with type
40 SHT_LLVM_ADDRSIG) to improve Identical Code Folding (ICF). Combined with the
41 ``-faddrsig`` compiler option added to Clang 7, lld's ``--icf=all`` can now
42 safely merge functions and data to generate smaller outputs than before.
44 * Improved ``--gdb-index`` so that it is faster (`r336790
45 <https://reviews.llvm.org/rL336790>`_) and uses less memory (`r336672
46 <https://reviews.llvm.org/rL336672>`_).
48 * Reduced memory usage of ``--compress-debug-sections`` (`r338913
49 <https://reviews.llvm.org/rL338913>`_).
51 * Added linker script OVERLAY support (`r335714 <https://reviews.llvm.org/rL335714>`_).
53 * Added ``--warn-backref`` to make it easy to identify command line option order
54 that doesn't work with GNU linkers (`r329636 <https://reviews.llvm.org/rL329636>`_)
56 * Added ld.lld.1 man page (`r324512 <https://reviews.llvm.org/rL324512>`_).
58 * Added support for multi-GOT.
60 * Added support for MIPS position-independent executable (PIE).
62 * Fixed MIPS TLS GOT entries for local symbols in shared libraries.
64 * Fixed calculation of MIPS GP relative relocations in case of relocatable
67 * Added support for PPCv2 ABI.
69 * Removed an incomplete support of PPCv1 ABI.
71 * Added support for Qualcomm Hexagon ISA.
73 * Added the following flags: ``--apply-dynamic-relocs``, ``--check-sections``,
74 ``--cref``, ``--just-symbols``, ``--keep-unique``,
75 ``--no-allow-multiple-definition``, ``--no-apply-dynamic-relocs``,
76 ``--no-check-sections``, ``--no-gnu-unique, ``--no-pic-executable``,
77 ``--no-undefined-version``, ``--no-warn-common``, ``--pack-dyn-relocs=relr``,
78 ``--pop-state``, ``--print-icf-sections``, ``--push-state``,
79 ``--thinlto-index-only``, ``--thinlto-object-suffix-replace``,
80 ``--thinlto-prefix-replace``, ``--warn-backref``, ``-z combreloc``, ``-z
81 copyreloc``, ``-z initfirst``, ``-z keep-text-section-prefix``, ``-z lazy``,
82 ``-z noexecstack``, ``-z relro``, ``-z retpolineplt``, ``-z text``
87 * Improved correctness of exporting mangled stdcall symbols.
89 * Completed support for ARM64 relocations.
91 * Added support for outputting PDB debug info for MinGW targets.
93 * Improved compatibility of output binaries with GNU binutils objcopy/strip.
95 * Sped up PDB file creation.
97 * Changed section layout to improve compatibility with link.exe.
99 * Added the following flags: ``--color-diagnostics={always,never,auto}``,
100 ``--no-color-diagnostics``, ``/brepro``, ``/debug:full``, ``/debug:ghash``,
101 ``/guard:cf``, ``/guard:longjmp``, ``/guard:nolongjmp``, ``/integritycheck``,
102 ``/order``, ``/pdbsourcepath``, ``/timestamp``