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diff --git a/contrib/llvm/tools/lld/docs/ReleaseNotes.rst b/contrib/llvm/tools/lld/docs/ReleaseNotes.rst index aab52573d925..76207fec11ac 100644 --- a/contrib/llvm/tools/lld/docs/ReleaseNotes.rst +++ b/contrib/llvm/tools/lld/docs/ReleaseNotes.rst @@ -1,19 +1,22 @@ ======================= -lld 8.0.0 Release Notes +lld 9.0.0 Release Notes ======================= .. contents:: :local: +.. warning:: + These are in-progress notes for the upcoming LLVM 9.0.0 release. + Release notes for previous releases can be found on + `the Download Page <https://releases.llvm.org/download.html>`_. + Introduction ============ -lld is a high-performance linker that supports ELF (Unix), COFF (Windows), -Mach-O (macOS), MinGW and WebAssembly. lld is command-line-compatible with -GNU linkers and Microsoft link.exe and is significantly faster than the -system default linkers. - -lld 8.0.0 has lots of feature improvements and bug fixes. +This document contains the release notes for the lld linker, release 9.0.0. +Here we describe the status of lld, including major improvements +from the previous release. All lld releases may be downloaded +from the `LLVM releases web site <https://llvm.org/releases/>`_. Non-comprehensive list of changes in this release ================================================= @@ -21,101 +24,50 @@ Non-comprehensive list of changes in this release ELF Improvements ---------------- -* lld now supports RISC-V. (`r339364 - <https://reviews.llvm.org/rL339364>`_) - -* Default image base address has changed from 65536 to 2 MiB for i386 - and 4 MiB for AArch64 to make lld-generated executables work better - with automatic superpage promotion. FreeBSD can promote contiguous - non-superpages to a superpage if they are aligned to the superpage - size. (`r342746 <https://reviews.llvm.org/rL342746>`_) - -* lld now attempts to place a ``.note`` segment in the first page of a - generated file, so that you can find some important information - (``.note.gnu.build-id`` in particular) in a core file even if a core - file is truncated by ulimit. - (`r349524 <https://reviews.llvm.org/rL349524>`_) - -* lld now reports an error if ``_GLOBAL_OFFSET_TABLE_`` symbol is - defined by an input object file, as the symbol is supposed to be - synthesized by the linker. - (`r347854 <https://reviews.llvm.org/rL347854>`_) - -* lld/Hexagon can now link Linux kernel and musl libc for Qualcomm - Hexagon ISA. - -* Initial MSP430 ISA support has landed. - -* lld now uses the ``sigrie`` instruction as a trap instruction for - MIPS targets. +* ld.lld now has typo suggestions for flags: + ``$ ld.lld --call-shared`` now prints + ``unknown argument '--call-shared', did you mean '--call_shared'``. -* lld now creates a TLS segment for AArch64 with a slightly larger - alignment requirement, so that the loader makes a few bytes room - before each TLS segment at runtime. The aim of this change is to - make room to accomodate nonstandard Android TLS slots while keeping - the compatibility with the standard AArch64 ABI. - (`r350681 <https://reviews.llvm.org/rL350681>`_) - -* The following flags have been added: ``--call-graph-profile``, - ``--no-call-graph-profile``, ``--warn-ifunc-textrel``, - ``-z interpose``, ``-z global``, ``-z nodefaultlib`` +* ... COFF Improvements ----------------- -* PDB GUID is set to hash of PDB contents instead to a random byte - sequence for build reproducibility. - -* ``/pdbsourcepath:`` is now also used to make ``"cwd"``, ``"exe"``, ``"pdb"`` - in the env block of PDB outputs absolute if they are relative, and to make - paths to obj files referenced in PDB outputs absolute if they are relative. - Together with the previous item, this makes it possible to generate - executables and PDBs that are fully deterministic and independent of the - absolute path to the build directory, so that different machines building - the same code in different directories can produce exactly the same output. +* Like the ELF driver, lld-link now has typo suggestions for flags. -* The following flags have been added: ``/force:multiple`` +* lld-link now correctly reports duplicate symbol errors for obj files + that were compiled with /Gy. -* lld now can link against import libraries produced by GNU tools. +* lld-link now correctly reports duplicate symbol errors when several res + input files define resources with the same type, name, and language. + This can be demoted to a warning using ``/force:multipleres``. -* lld can create thunks for ARM and ARM64, to allow linking larger images - (over 16 MB for ARM and over 128 MB for ARM64) - -* Several speed and memory usage improvements. +* Having more than two ``/natvis:`` now works correctly; it used to not + work for larger binaries before. -* lld now creates debug info for typedefs. +* Undefined symbols are now printed only in demangled form. Pass + ``/demangle:no`` to see raw symbol names instead. -* lld can now link obj files produced by ``cl.exe /Z7 /Yc``. +* The following flags have been added: ``/functionpadmin``, ``/swaprun:``, + ``/threads:no`` -* lld now understands ``%_PDB%`` and ``%_EXT%`` in ``/pdbaltpath:``. +* Several speed and memory usage improvements. -* Undefined symbols are now printed in demangled form in addition to raw form. +* ... MinGW Improvements ------------------ -* lld can now automatically import data variables from DLLs without the - use of the dllimport attribute. - -* lld can now use existing normal MinGW sysroots with import libraries and - CRT startup object files for GNU binutils. lld can handle most object - files produced by GCC, and thus works as a drop-in replacement for - ld.bfd in such environments. (There are known issues with linking crtend.o - from GCC in setups with DWARF exceptions though, where object files are - linked in a different order than with GNU ld, inserting a DWARF exception - table terminator too early.) +* lld now correctly links crtend.o as the last object file, handling + terminators for the sections such as .eh_frame properly, fixing + DWARF exception handling with libgcc and gcc's crtend.o. -* lld now supports COFF embedded directives for linking to nondefault - libraries, just like for the normal COFF target. +MachO Improvements +------------------ -* Actually generate a codeview build id signature, even if not creating a PDB. - Previously, the ``--build-id`` option did not actually generate a build id - unless ``--pdb`` was specified. +* Item 1. WebAssembly Improvements ------------------------ -* Add initial support for creating shared libraries (-shared). - Note: The shared library format is still under active development and may - undergo significant changes in future versions. - See: https://github.com/WebAssembly/tool-conventions/blob/master/DynamicLinking.md +* ... |