e1689689d8
Previously, in r320472, I moved the calculation of section offsets and sizes for compressed debug sections into maybeCompress, which happens before assignAddresses, so that the compression had the required information. However, I failed to take account of relocations that patch such sections. This had two effects: 1. A race condition existed when a debug section referred to a different debug section (see PR35788). 2. References to symbols in non-debug sections would be patched incorrectly. This is because the addresses of such symbols are not calculated until after assignAddresses (this was a partial regression caused by r320472, but they could still have been broken before, in the event that a custom layout was used in a linker script). assignAddresses does not need to know about the output section size of non-allocatable sections, because they do not affect the value of Dot. This means that there is no longer a reason not to support custom layout of compressed debug sections, as far as I'm aware. These two points allow for delaying when maybeCompress can be called, removing the need for the loop I previously added to calculate the section size, and therefore the race condition. Furthermore, by delaying, we fix the issues of relocations getting incorrect symbol values, because they have now all been finalized. llvm-svn: 321986
LLVM Linker (lld)
This directory and its subdirectories contain source code for the LLVM Linker, a modular cross platform linker which is built as part of the LLVM compiler infrastructure project.
lld is open source software. You may freely distribute it under the terms of the license agreement found in LICENSE.txt.
Benchmarking
In order to make sure various developers can evaluate patches over the same tests, we create a collection of self contained programs.
It is hosted at https://s3-us-west-2.amazonaws.com/linker-tests/lld-speed-test.tar.xz
The current sha256 is 10eec685463d5a8bbf08d77f4ca96282161d396c65bd97dc99dbde644a31610f.