[all-commits] [llvm/llvm-project] 20ee72: tsan: don't call dlsym during exit

[Dmitry Vyukov via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 20ee72d4ccb17c6f32641c690fa129475427ae45
      https://github.com/llvm/llvm-project/commit/20ee72d4ccb17c6f32641c690fa129475427ae45
  Author: Dmitry Vyukov <dvyukov at google.com>
  Date:   2021-09-22 (Wed, 22 Sep 2021)

  Changed paths:
    M compiler-rt/lib/tsan/rtl/tsan_interface.h
    M compiler-rt/lib/tsan/rtl/tsan_platform_posix.cpp
    M compiler-rt/lib/tsan/rtl/tsan_rtl.cpp
    M compiler-rt/lib/tsan/rtl/tsan_rtl.h
    A compiler-rt/test/tsan/signal_exit.cpp

  Log Message:
  -----------
  tsan: don't call dlsym during exit

dlsym calls into dynamic linker which calls malloc and other things.
It's problematic to do it during the actual exit, because
it can happen from a singal handler or from within the runtime
after we reported the first bug, etc.
See https://github.com/google/sanitizers/issues/1440 for an example
(captured in the added test).
Initialize the callbacks during startup instead.

Depends on D110159.

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D110166