| commit | 8eb99bbe6e8878bfd73fb301899ced6bb5dfff38 | [log] [tgz] |
|---|---|---|
| author | Martin Storsjö <martin@martin.st> | Thu Jan 23 09:15:47 2025 +0200 |
| committer | GitHub <noreply@github.com> | Thu Jan 23 09:15:47 2025 +0200 |
| tree | 49e370c383b2cfc7bc4cc1d891243a9f641d95c6 | |
| parent | 3fb8c5b43195d6e11ff0557d07e75700343d369f [diff] |
Reland [LLD] [COFF] Fix linking MSVC generated implib header objects (#123916) ecb5ea6a266d5cc4e05252f6db4c73613b73cc3b tried to fix cases when LLD links what seems to be import library header objects from MSVC. However, the fix seems incorrect; the review at https://reviews.llvm.org/D133627 concluded that if this (treating this kind of symbol as a common symbol) is what link.exe does, it's fine. However, this is most probably not what link.exe does. The symbol mentioned in the commit message of ecb5ea6a266d5cc4e05252f6db4c73613b73cc3b would be a common symbol with a size of around 3 GB; this is not what might have been intended. That commit tried to avoid running into the error ".idata$4 should not refer to special section 0"; that issue is fixed for a similar style of section symbols in 4a4a8a1476b1386b523dc5b292ba9a5a6748a9cf. Therefore, revert ecb5ea6a266d5cc4e05252f6db4c73613b73cc3b and extend the fix from 4a4a8a1476b1386b523dc5b292ba9a5a6748a9cf to also work for the section symbols in MSVC generated import libraries. The main detail about them, is that for symbols of type IMAGE_SYM_CLASS_SECTION, the Value field is not an offset, but it is an optional set of flags, corresponding to the Characteristics of the section header (although it may be empty). This is a reland of a previous version of this commit, earlier merged in 9457418e66766d8fafc81f85eb8045986220ca3e / #122811. The previous version failed tests when run with address sanitizer. The issue was that the synthesized coff_symbol_generic object actually will be used to access a full coff_symbol16 or coff_symbol32 struct, see DefinedCOFF::getCOFFSymbol. Therefore, we need to make a copy of the full size of either of them.
Welcome to the LLVM project!
This repository contains the source code for LLVM, a toolkit for the construction of highly optimized compilers, optimizers, and run-time environments.
The LLVM project has multiple components. The core of the project is itself called “LLVM”. This contains all of the tools, libraries, and header files needed to process intermediate representations and convert them into object files. Tools include an assembler, disassembler, bitcode analyzer, and bitcode optimizer.
C-like languages use the Clang frontend. This component compiles C, C++, Objective-C, and Objective-C++ code into LLVM bitcode -- and from there into object files, using LLVM.
Other components include: the libc++ C++ standard library, the LLD linker, and more.
Consult the Getting Started with LLVM page for information on building and running LLVM.
For information on how to contribute to the LLVM project, please take a look at the Contributing to LLVM guide.
Join the LLVM Discourse forums, Discord chat, LLVM Office Hours or Regular sync-ups.
The LLVM project has adopted a code of conduct for participants to all modes of communication within the project.