[runtimes] Remove FOO_TARGET_TRIPLE, FOO_SYSROOT and FOO_GCC_TOOLCHAIN
Instead, folks can use the equivalent variables provided by CMake
to set those. This removal aims to reduce complexity and potential
for confusion when setting the target triple for building the runtimes,
and make it correct when `CMAKE_OSX_ARCHITECTURES` is used (right now
both `-arch` and `--target=` will end up being passed, which is downright
incorrect).
Differential Revision: https://reviews.llvm.org/D112155
NOKEYCHECK=True
GitOrigin-RevId: 3ee0cec88effc88285732c8bec2a8f0e4e37c0b1
diff --git a/docs/BuildingLibcxx.rst b/docs/BuildingLibcxx.rst
index 0e536cc..aa26a22 100644
--- a/docs/BuildingLibcxx.rst
+++ b/docs/BuildingLibcxx.rst
@@ -136,7 +136,7 @@
If you are running in an MSYS2 shell and you have installed the
MSYS2-provided clang package (which defaults to a non-MSVC target), you
-should add e.g. ``-DLIBCXX_TARGET_TRIPLE=x86_64-windows-msvc`` (replacing
+should add e.g. ``-DCMAKE_CXX_COMPILER_TARGET=x86_64-windows-msvc`` (replacing
``x86_64`` with the architecture you're targeting) to the ``cmake`` command
line above. This will instruct ``check-cxx`` to use the right target triple
when invoking ``clang++``.