From 4930eb6de0b65f1543bd09e403ce4cc8b1d4dd65 Mon Sep 17 00:00:00 2001
From: Eric Christopher <echristo@gmail.com>
Date: Thu, 18 Sep 2025 11:45:40 -0700
Subject: [PATCH] Add documentation about CMAKE_OSX_SYSROOT so that folks
 bringing up on OSX can have a clean test run.

---
 llvm/docs/CMake.rst | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/llvm/docs/CMake.rst b/llvm/docs/CMake.rst
index 438a84d39ed66..7e95545425f2d 100644
--- a/llvm/docs/CMake.rst
+++ b/llvm/docs/CMake.rst
@@ -1200,3 +1200,14 @@ Windows
   When compiling with clang-cl, CMake may use ``llvm-mt`` as the Manifest Tool
   when available. ```llvm-mt``` is only present when libxml2 is found at build-time.
   To ensure using Microsoft's Manifest Tool set `CMAKE_MT=mt`.
+
+Apple/OSX
+---------
+
+**CMAKE_OSX_SYSROOT**:STRING
+  When compiling for OSX, in order for the test suite to find libSystem to link
+  dylib tests you'll need to run CMake with ```xcrun --show-sdk-path``` as the
+  string to pass in so that the testsuite can find your os libraries.
+
+  This will show up as ```ld: library not found for -lSystem``` when running
+  tests.