[PATCH] D53906: [ELF] Allow configuring the TLS layout for an Android executable

[Ryan Prichard via Phabricator via llvm-commits]

rprichard added a comment.

Android/Bionic currently doesn't have ELF TLS support, so no existing binaries are affected. I'm working on adding support for ELF TLS to Android, but Android's existing use of the thread pointer conflicts with the ordinary ELF TLS ABI.

Currently, C/C++ variables declared with __thread/thread_local are implemented using emutls. The compiler generates calls to functions in libgcc/libcompiler-rt.

Part of my motivation for PT_ANDROID_TLS_TPOFF is to detect binaries that weren't linked with this new linker flag and refuse to run them. Otherwise, programs would run but silently corrupt memory.


Repository:
  rLLD LLVM Linker

https://reviews.llvm.org/D53906