tree eba6e902441fb593bebfa9a0a0e0afb892c77429
parent 8ee1c59ffa3c4e2635817f65894f4250cf7abf8f
author Petr Hosek <phosek@chromium.org> 1549310546 +0000
committer Petr Hosek <phosek@chromium.org> 1549310546 +0000

[CMake] Support CMake variables for setting target, sysroot and toolchain

CMake has a standard way of setting target triple, sysroot and external
toolchain through CMAKE_<LANG>_COMPILER_TARGET, CMAKE_SYSROOT and
CMAKE_<LANG>_COMPILER_EXTERNAL_TOOLCHAIN. These are turned into
corresponding --target=, --sysroot= and --gcc-toolchain= variables add
included appended to CMAKE_<LANG>_FLAGS.

libunwind, libc++abi, libc++ provides their own mechanism through
<PROJECT>_TARGET_TRIPLE, <PROJECT>_SYSROOT and <PROJECT>_GCC_TOOLCHAIN
variables. These are also passed to lit via lit.site.cfg, and lit config
uses these to set the corresponding compiler flags when building tessts.

This means that there are two different ways of setting target, sysroot
and toolchain, but only one is properly supported in lit. This change
extends CMake build for libunwind, libc++abi and libc++ to also support
the CMake variables in addition to project specific ones in lit.

Differential Revision: https://reviews.llvm.org/D57670

git-svn-id: https://llvm.org/svn/llvm-project/libunwind/trunk@353084 91177308-0d34-0410-b5e6-96231b3b80d8