[all-commits] [llvm/llvm-project] 57fc8e: Reland "Enable `-funwind-tables` flag when buildin...

[Sergej Jaskiewicz via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 57fc8ecdbaa7fbb1a13907ca3f7a3cb9f9459d27
      https://github.com/llvm/llvm-project/commit/57fc8ecdbaa7fbb1a13907ca3f7a3cb9f9459d27
  Author: Sergej Jaskiewicz <jaskiewiczs at icloud.com>
  Date:   2019-12-11 (Wed, 11 Dec 2019)

  Changed paths:
    M libunwind/CMakeLists.txt
    M libunwind/cmake/config-ix.cmake
    M libunwind/test/CMakeLists.txt
    M libunwind/test/libunwind/test/config.py
    M libunwind/test/lit.site.cfg.in
    M libunwind/test/signal_frame.pass.cpp

  Log Message:
  -----------
  Reland "Enable `-funwind-tables` flag when building libunwind"

Summary:
Relands https://reviews.llvm.org/D70815.

The original commit set `CMAKE_TRY_COMPILE_TARGET_TYPE` to
`STATIC_LIBRARY` globally in libunwind/CMakeLists.txt, which effectively
disabled the linking step in CMake checks.

This broke some builds (see 938c70b86c7d2165f8c28d5700e9c1ac1263307e).

Here we set CMAKE_TRY_COMPILE_TARGET_TYPE to
STATIC_LIBRARY only when checking for presence of the `-funwind-tables`
flag, and then set it back to the original value so it doesn't affect
other checks.

Reviewers: mstorsjo, jfb

Subscribers: mgorny, christof, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D71117