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Diffstat (limited to 'lld/docs/ReleaseNotes.rst')
| -rw-r--r-- | lld/docs/ReleaseNotes.rst | 148 |
1 files changed, 138 insertions, 10 deletions
diff --git a/lld/docs/ReleaseNotes.rst b/lld/docs/ReleaseNotes.rst index 82683801fad9..672759fdf6b3 100644 --- a/lld/docs/ReleaseNotes.rst +++ b/lld/docs/ReleaseNotes.rst @@ -30,45 +30,173 @@ ELF Improvements (`D107317 <https://reviews.llvm.org/D107317>`_) * ``--why-extract`` has been added to query why archive members/lazy object files are extracted. (`D109572 <https://reviews.llvm.org/D109572>`_) -* ``e_entry`` no longer falls back to the address of ``.text`` if the entry symbol does not exist. - Instead, a value of 0 will be written. - (`D110014 <https://reviews.llvm.org/D110014>`_) * If ``-Map`` is specified, ``--cref`` will be printed to the specified file. (`D114663 <https://reviews.llvm.org/D114663>`_) +* ``-z bti-report`` and ``-z cet-report`` are now supported. + (`D113901 <https://reviews.llvm.org/D113901>`_) +* ``--lto-pgo-warn-mismatch`` has been added. + (`D104431 <https://reviews.llvm.org/D104431>`_) +* Archives without an index (symbol table) are now supported and work with + ``--warn-backrefs``. One may build such an archive with ``llvm-ar rcS + [--thin]`` to save space. + (`D117284 <https://reviews.llvm.org/D117284>`_) + The archive index may be `entirely ignored <https://reviews.llvm.org/D119074>`_ + in a future release. * No longer deduplicate local symbol names at the default optimization level of ``-O1``. This results in a larger ``.strtab`` (usually less than 1%) but a faster link - time. Use optimization level ``-O2`` to restore the deduplication. + time. Use optimization level ``-O2`` to restore the deduplication. The ``-O2`` + deduplication may be dropped in the future to help parallel ``.symtab`` write. +* In relocatable output, relocations to discarded symbols now use tombstone + values. + (`D116946 <https://reviews.llvm.org/D116946>`_) +* Orphan section placement now picks a more suitable segment. Previously the + algorithm might pick a readonly segment for a writable orphan section and make + the segment writable. + (`D111717 <https://reviews.llvm.org/D111717>`_) +* An empty output section moved by an ``INSERT`` comment now gets appropriate + flags. + (`D118529 <https://reviews.llvm.org/D118529>`_) +* Negation in a memory region attribute is now correctly handled. + (`D113771 <https://reviews.llvm.org/D113771>`_) +* ``--compress-debug-sections=zlib`` is now run in parallel. ``{clang,gcc} -gz`` link + actions are significantly faster. + (`D117853 <https://reviews.llvm.org/D117853>`_) +* "relocation out of range" diagnostics and a few uncommon diagnostics + now report an object file location beside a source file location. + (`D112518 <https://reviews.llvm.org/D117853>`_) +* The write of ``.rela.dyn`` and ``SHF_MERGE|SHF_STRINGS`` sections (e.g. + ``.debug_str``) is now run in parallel. Architecture specific changes: +* The AArch64 port now supports adrp+ldr and adrp+add optimizations. + ``--no-relax`` can suppress the optimization. + (`D112063 <https://reviews.llvm.org/D112063>`_) + (`D117614 <https://reviews.llvm.org/D117614>`_) * The x86-32 port now supports TLSDESC (``-mtls-dialect=gnu2``). (`D112582 <https://reviews.llvm.org/D112582>`_) * The x86-64 port now handles non-RAX/non-adjacent ``R_X86_64_GOTPC32_TLSDESC`` and ``R_X86_64_TLSDESC_CALL`` (``-mtls-dialect=gnu2``). (`D114416 <https://reviews.llvm.org/D114416>`_) +* The x86-32 and x86-64 ports now support mixed TLSDESC and TLS GD, i.e. mixing + objects compiled with and without ``-mtls-dialect=gnu2`` referencing the same + TLS variable is now supported. + (`D114416 <https://reviews.llvm.org/D114416>`_) * For x86-64, ``--no-relax`` now suppresses ``R_X86_64_GOTPCRELX`` and ``R_X86_64_REX_GOTPCRELX`` GOT optimization (`D113615 <https://reviews.llvm.org/D113615>`_) +* ``R_X86_64_PLTOFF64`` is now supported. + (`D112386 <https://reviews.llvm.org/D112386>`_) +* ``R_AARCH64_NONE``, ``R_PPC_NONE``, and ``R_PPC64_NONE`` in input REL + relocation sections are now supported. Breaking changes ---------------- -* ... +* ``e_entry`` no longer falls back to the address of ``.text`` if the entry symbol does not exist. + Instead, a value of 0 will be written. + (`D110014 <https://reviews.llvm.org/D110014>`_) +* ``--lto-pseudo-probe-for-profiling`` has been removed. In LTO, the compiler + enables this feature automatically. + (`D110209 <https://reviews.llvm.org/D110209>`_) +* Use of ``--[no-]define-common``, ``-d``, ``-dc``, and ``-dp`` will now get a + warning. They will be removed or ignored in 15.0.0. + (`llvm-project#53660 <https://github.com/llvm/llvm-project/issues/53660>`_) COFF Improvements ----------------- -* ... +* Correctly handle a signed immediate offset in ARM64 adr/adrp relocations. + (`D114347 <https://reviews.llvm.org/D114347>`_) + +* Omit section and label symbols from the symbol table. + (`D113866 <https://reviews.llvm.org/D113866>`_) MinGW Improvements ------------------ -* ... +* ``--heap`` is now handled. + (`D118405 <https://reviews.llvm.org/D118405>`_) -MachO Improvements ------------------- +Mach-O Improvements +------------------- -* Item 1. +* The ``ld64.lld.darwinnew`` symlink has been removed. Use ``ld64.lld`` to + invoke the Mach-O backend from now on. Moreover, the symlink + ``ld64.lld.darwinold`` -- and the old Mach-O LLD code that it pointed to -- + have been removed. (`D114842 <https://reviews.llvm.org/D114842>`_) +* The "cannot export hidden symbol" error has been downgraded to a warning. + (`D107011 <https://reviews.llvm.org/D107011>`_) +* Common bitcode symbols are now supported. + (`D107027 <https://reviews.llvm.org/D107027>`_) +* Weak references in bitcode are now supported. + (`D115949 <https://reviews.llvm.org/D115949>`_) +* Thunk insertion now works more reliably. + (`D108897 <https://reviews.llvm.org/D108897>`_, + `D108924 <https://reviews.llvm.org/D108924>`_, + `D109079 <https://reviews.llvm.org/D109079>`_, + `D116705 <https://reviews.llvm.org/D116705>`_) +* ``-ObjC`` now loads archive members before the symbol resolution phase. + (`D108781 <https://reviews.llvm.org/D108781>`_) +* ``-oso_prefix`` is now supported. + (`D112291 <https://reviews.llvm.org/D112291>`_) +* Properly encode binaries with zero exported symbols. Tools like + ``codesign_allocate`` no longer choke on those binaries. + (`D112589 <https://reviews.llvm.org/D112589>`_) +* We no longer treat architecture mismatches as a fatal error. Use + ``-arch_errors_fatal`` if that behavior is still desired. + (`D113082 <https://reviews.llvm.org/D113082>`_) +* Several performance improvements were done to speed LLD up on projects with + a lot of framework flags and library lookups. Large Swift-based projects + will benefit significantly. + (`D113073 <https://reviews.llvm.org/D113073>`_, + `D113063 <https://reviews.llvm.org/D113063>`_, + `D113153 <https://reviews.llvm.org/D113153>`_, + `D113235 <https://reviews.llvm.org/D113235>`_) +* Several memory-reduction optimizations were done to reduce LLD's RSS + footprint. + (`D113813 <https://reviews.llvm.org/D113813>`_, + `D113818 <https://reviews.llvm.org/D113818>`_) +* Symbol patterns from ``-[un]exported_symbols_list`` are now processed in + parallel. (`D113820 <https://reviews.llvm.org/D113820>`_) +* ``.weak_def_can_be_hidden`` symbols can now be exported. + (`D113167 <https://reviews.llvm.org/D113167>`_) +* ``-S`` -- to omit debug info -- is now handled. + (`D112594 <https://reviews.llvm.org/D112594>`_) +* ``-v`` now writes to stderr instead of stdout. + (`D113020 <https://reviews.llvm.org/D113020>`_) +* Private externs with GOT relocations are now marked as LOCAL in the indirect + symbol table. This allows ``strip -x`` to remove more symbols. + (`D111852 <https://reviews.llvm.org/D111852>`_) +* We no longer generate bogus addresses when ``__TEXT,__gcc_except_tab`` is + renamed. (`D113582 <https://reviews.llvm.org/D113582>`_) +* Unreferenced weak dylib symbols no longer trigger fetches from an archive. + (`D115092 <https://reviews.llvm.org/D115092>`_) +* ``$ld$hide`` symbols are now supported. + (`D115775 <https://reviews.llvm.org/D115775>`_) +* Symbols imported via ``-weak_framework`` are now properly marked as weak refs. + (`D114397 <https://reviews.llvm.org/D114397>`_) +* ``--warn-dylib-install-name`` and ``--no-warn-dylib-install-name`` were added + to toggle LLD-specific warnings around the use of ``-install_name``. + (`D113534 <https://reviews.llvm.org/D113534>`_) +* Passing both ``--icf=all`` and ``-no_deduplicate`` no longer results in a + warning. (`D110672 <https://reviews.llvm.org/D110672>`_) +* ICF now deduplicates functions with (identical) unwind info too. + (`D109946 <https://reviews.llvm.org/D109946>`_) +* We now support ordering sections based on call graph profile data. + (`D112164 <https://reviews.llvm.org/D112164>`_) +* Map file output now proceeds in parallel with output of the binary. + (`D117069 <https://reviews.llvm.org/D117069>`_) +* The map file now contains dead-stripped symbols too. + (`D114737 <https://reviews.llvm.org/D114737>`_) +* Multiple TLV sections with different alignments are now handled properly. + (`D116263 <https://reviews.llvm.org/D116263>`_) +* ``--start-lib`` and ``--end-lib`` are now supported. + (`D116913 <https://reviews.llvm.org/D116913>`_) +* ``-noall_load`` is now supported. + (`D117629 <https://reviews.llvm.org/D117629>`_) +* ``-add_empty_section`` is now supported. + (`D117749 <https://reviews.llvm.org/D117749>`_) WebAssembly Improvements ------------------------ |