[compiler-rt] [compiler-rt] Propagate sysroot from CMake to msan tests (PR #132299)

[via llvm-commits]

https://github.com/zeroomega created https://github.com/llvm/llvm-project/pull/132299

Some msan tests requires rpc/xdr.h, which is no longer available in some newer glibc. In build systems with hermetic sysroot set through CMake, this issue can be solved by setting the sysroot to CMAKE_SYSROOT for these tests. This patch implements it.

>From 5c8a61c216dba6fcb1a8b2da0a3d064a4ca8b4e4 Mon Sep 17 00:00:00 2001
From: Haowei Wu <haowei at google.com>
Date: Thu, 20 Mar 2025 15:14:10 -0700
Subject: [PATCH] [compiler-rt] Propagate sysroot from CMake to msan tests

Some msan tests requires rpc/xdr.h, which is no longer available
in some newer glibc. In build systems with hermetic sysroot set through
CMake, this issue can be solved by setting the sysroot to CMAKE_SYSROOT
for these tests. This patch implements it.
---
 compiler-rt/test/msan/lit.cfg.py         | 4 ++++
 compiler-rt/test/msan/lit.site.cfg.py.in | 1 +
 2 files changed, 5 insertions(+)

diff --git a/compiler-rt/test/msan/lit.cfg.py b/compiler-rt/test/msan/lit.cfg.py
index 361be79e2557e..7282d29340201 100644
--- a/compiler-rt/test/msan/lit.cfg.py
+++ b/compiler-rt/test/msan/lit.cfg.py
@@ -17,6 +17,10 @@
         "-fno-optimize-sibling-calls",
     ]
     + [config.target_cflags]
+    + [
+        "--sysroot",
+        config.cmake_sysroot
+    ] if config.cmake_sysroot and config.host_os == "Linux" else []
     + config.debug_info_flags
 )
 # Some Msan tests leverage backtrace() which requires libexecinfo on FreeBSD.
diff --git a/compiler-rt/test/msan/lit.site.cfg.py.in b/compiler-rt/test/msan/lit.site.cfg.py.in
index 47264d0986946..41231359692ed 100644
--- a/compiler-rt/test/msan/lit.site.cfg.py.in
+++ b/compiler-rt/test/msan/lit.site.cfg.py.in
@@ -6,6 +6,7 @@ config.target_cflags = "@MSAN_TEST_TARGET_CFLAGS@"
 config.target_arch = "@MSAN_TEST_TARGET_ARCH@"
 config.use_lld = @MSAN_TEST_USE_LLD@
 config.use_thinlto = @MSAN_TEST_USE_THINLTO@
+config.cmake_sysroot = "@CMAKE_SYSROOT@"
 
 # Load common config for all compiler-rt lit tests.
 lit_config.load_config(config, "@COMPILER_RT_BINARY_DIR@/test/lit.common.configured")