diff --git a/lldb/test/Shell/helper/build.py b/lldb/test/Shell/helper/build.py
--- a/lldb/test/Shell/helper/build.py
+++ b/lldb/test/Shell/helper/build.py
@@ -73,6 +73,14 @@
     help="Include and link GNUstep libobjc2 (Windows and Linux only)",
 )
 
+parser.add_argument(
+    "--sysroot",
+    metavar="directory",
+    dest="sysroot",
+    required=False,
+    help="If specified, a sysroot to be passed via --sysroot",
+)
+
 if sys.platform == "darwin":
     parser.add_argument(
         "--apple-sdk",
@@ -305,6 +313,7 @@
             if args.objc_gnustep_dir
             else None
         )
+        self.sysroot = args.sysroot
 
     def _exe_file_name(self):
         assert self.mode != "compile"
@@ -761,6 +770,8 @@
                     args.extend(
                         ["-Xclang", "-gcodeview", "-Xclang", "--dependent-lib=msvcrtd"]
                     )
+        elif self.sysroot:
+            args.extend(["--sysroot", self.sysroot])
 
         if self.std:
             args.append("-std={0}".format(self.std))
@@ -797,6 +808,8 @@
                 args.extend(
                     ["-fuse-ld=lld-link", "-g", "-Xclang", "--dependent-lib=msvcrtd"]
                 )
+        elif self.sysroot:
+            args.extend(["--sysroot", self.sysroot])
 
         return ("linking", self._obj_file_names(), self._exe_file_name(), None, args)
 
diff --git a/lldb/test/Shell/helper/toolchain.py b/lldb/test/Shell/helper/toolchain.py
--- a/lldb/test/Shell/helper/toolchain.py
+++ b/lldb/test/Shell/helper/toolchain.py
@@ -47,6 +47,8 @@
         build_script_args.append(
             '--objc-gnustep-dir="{0}"'.format(config.objc_gnustep_dir)
         )
+    if config.cmake_sysroot:
+        build_script_args.append("--sysroot={0}".format(config.cmake_sysroot))
 
     lldb_init = _get_lldb_init_path(config)
 
@@ -160,6 +162,9 @@
     # The clang module cache is used for building inferiors.
     host_flags += ["-fmodules-cache-path={}".format(config.clang_module_cache)]
 
+    if config.cmake_sysroot:
+        host_flags += ["--sysroot={}".format(config.cmake_sysroot)]
+
     host_flags = " ".join(host_flags)
     config.substitutions.append(("%clang_host", "%clang " + host_flags))
     config.substitutions.append(("%clangxx_host", "%clangxx " + host_flags))
diff --git a/lldb/test/Shell/lit.site.cfg.py.in b/lldb/test/Shell/lit.site.cfg.py.in
--- a/lldb/test/Shell/lit.site.cfg.py.in
+++ b/lldb/test/Shell/lit.site.cfg.py.in
@@ -13,6 +13,7 @@
 # Since it comes from the command line, it may have backslashes which
 # should not need to be escaped.
 config.lldb_lit_tools_dir = lit_config.substitute(r"@LLDB_LIT_TOOLS_DIR@")
+config.cmake_sysroot = lit_config.substitute("@CMAKE_SYSROOT@")
 config.target_triple = "@LLVM_TARGET_TRIPLE@"
 config.python_executable = "@Python3_EXECUTABLE@"
 config.have_zlib = @LLVM_ENABLE_ZLIB@