[all-commits] [llvm/llvm-project] a32a2b: [clang][driver] Add <executable>/../include/c++/v1...

[Liviu Ionescu via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: a32a2b2ceb6b4c1bbcbcb39363c8dee44daf86ab
      https://github.com/llvm/llvm-project/commit/a32a2b2ceb6b4c1bbcbcb39363c8dee44daf86ab
  Author: Liviu Ionescu <ilg at livius.net>
  Date:   2023-11-20 (Mon, 20 Nov 2023)

  Changed paths:
    M clang/lib/Driver/ToolChains/Darwin.cpp
    M clang/test/Driver/darwin-header-search-libcxx.cpp

  Log Message:
  -----------
  [clang][driver] Add <executable>/../include/c++/v1 to include path on Darwin (#70817)

On macOS, when clang is invoked via a symlink, since the InstalledDir is
where the link is located, the C++ headers are not identified and the
default system headers from the SDK are used.

This can be undesirable if a toolchain is created by symlinking clang
into a directory and placing libc++ headers in that directory with the
intent of those headers overriding the SDK headers. This change solves
that problem by also looking for libc++ headers in the toolchain-relative
location of the executable symlink, if any.