diff --git a/lldb/packages/Python/lldbsuite/test/builders/builder.py b/lldb/packages/Python/lldbsuite/test/builders/builder.py
--- a/lldb/packages/Python/lldbsuite/test/builders/builder.py
+++ b/lldb/packages/Python/lldbsuite/test/builders/builder.py
@@ -122,8 +122,12 @@
 
     def getLibCxxArgs(self):
         if configuration.libcxx_include_dir and configuration.libcxx_library_dir:
-            return ["LIBCPP_INCLUDE_DIR={}".format(configuration.libcxx_include_dir),
-                    "LIBCPP_LIBRARY_DIR={}".format(configuration.libcxx_library_dir)]
+            libcpp_args = ["LIBCPP_INCLUDE_DIR={}".format(configuration.libcxx_include_dir),
+                           "LIBCPP_LIBRARY_DIR={}".format(configuration.libcxx_library_dir)]
+            if configuration.libcxx_include_target_dir:
+                libcpp_args.append("LIBCPP_INCLUDE_TARGET_DIR={}".format(
+                    configuration.libcxx_include_target_dir))
+            return libcpp_args
         return []
 
     def _getDebugInfoArgs(self, debug_info):
diff --git a/lldb/packages/Python/lldbsuite/test/configuration.py b/lldb/packages/Python/lldbsuite/test/configuration.py
--- a/lldb/packages/Python/lldbsuite/test/configuration.py
+++ b/lldb/packages/Python/lldbsuite/test/configuration.py
@@ -124,6 +124,7 @@
 lldb_libs_dir = None
 
 libcxx_include_dir = None
+libcxx_include_target_dir = None
 libcxx_library_dir = None
 
 # A plugin whose tests will be enabled, like intel-pt.
diff --git a/lldb/packages/Python/lldbsuite/test/dotest.py b/lldb/packages/Python/lldbsuite/test/dotest.py
--- a/lldb/packages/Python/lldbsuite/test/dotest.py
+++ b/lldb/packages/Python/lldbsuite/test/dotest.py
@@ -280,17 +280,15 @@
         logging.warning('No valid FileCheck executable; some tests may fail...')
         logging.warning('(Double-check the --llvm-tools-dir argument to dotest.py)')
 
-    configuration.libcxx_include_dir = args.libcxx_include_dir
-    configuration.libcxx_library_dir = args.libcxx_library_dir
     if args.libcxx_include_dir or args.libcxx_library_dir:
         if args.lldb_platform_name:
             logging.warning('Custom libc++ is not supported for remote runs: ignoring --libcxx arguments')
-        elif args.libcxx_include_dir and args.libcxx_library_dir:
-            configuration.libcxx_include_dir = args.libcxx_include_dir
-            configuration.libcxx_library_dir = args.libcxx_library_dir
-        else:
+        elif not (args.libcxx_include_dir and args.libcxx_library_dir):
             logging.error('Custom libc++ requires both --libcxx-include-dir and --libcxx-library-dir')
             sys.exit(-1)
+    configuration.libcxx_include_dir = args.libcxx_include_dir
+    configuration.libcxx_include_target_dir = args.libcxx_include_target_dir
+    configuration.libcxx_library_dir = args.libcxx_library_dir
 
     if args.channels:
         lldbtest_config.channels = args.channels
diff --git a/lldb/packages/Python/lldbsuite/test/dotest_args.py b/lldb/packages/Python/lldbsuite/test/dotest_args.py
--- a/lldb/packages/Python/lldbsuite/test/dotest_args.py
+++ b/lldb/packages/Python/lldbsuite/test/dotest_args.py
@@ -43,8 +43,12 @@
     if sys.platform == 'darwin':
         group.add_argument('--apple-sdk', metavar='apple_sdk', dest='apple_sdk', default="", help=textwrap.dedent(
             '''Specify the name of the Apple SDK (macosx, macosx.internal, iphoneos, iphoneos.internal, or path to SDK) and use the appropriate tools from that SDK's toolchain.'''))
-    group.add_argument('--libcxx-include-dir', help=textwrap.dedent('Specify the path to a custom libc++ include directory. Must be used in conjunction with --libcxx-library-dir.'))
-    group.add_argument('--libcxx-library-dir', help=textwrap.dedent('Specify the path to a custom libc++ library directory. Must be used in conjunction with --libcxx-include-dir.'))
+    group.add_argument('--libcxx-include-dir', help=textwrap.dedent(
+        'Specify the path to a custom libc++ include directory. Must be used in conjunction with --libcxx-library-dir.'))
+    group.add_argument('--libcxx-include-target-dir', help=textwrap.dedent(
+        'Specify the path to a custom libc++ include target directory to use in addition to --libcxx-include-dir. Optional.'))
+    group.add_argument('--libcxx-library-dir', help=textwrap.dedent(
+        'Specify the path to a custom libc++ library directory. Must be used in conjunction with --libcxx-include-dir.'))
     # FIXME? This won't work for different extra flags according to each arch.
     group.add_argument(
         '-E',
diff --git a/lldb/packages/Python/lldbsuite/test/make/Makefile.rules b/lldb/packages/Python/lldbsuite/test/make/Makefile.rules
--- a/lldb/packages/Python/lldbsuite/test/make/Makefile.rules
+++ b/lldb/packages/Python/lldbsuite/test/make/Makefile.rules
@@ -408,7 +408,10 @@
 ifeq (1,$(USE_LIBCPP))
 	ifneq ($(and $(LIBCPP_INCLUDE_DIR), $(LIBCPP_LIBRARY_DIR)),)
 		CXXFLAGS += -nostdlib++ -nostdinc++ -cxx-isystem $(LIBCPP_INCLUDE_DIR)
-		LDFLAGS += -L$(LLVM_LIBS_DIR) -Wl,-rpath,$(LIBCPP_LIBRARY_DIR) -lc++
+		ifneq "$(LIBCPP_INCLUDE_TARGET_DIR)" ""
+				CXXFLAGS += -cxx-isystem $(LIBCPP_INCLUDE_TARGET_DIR)
+		endif
+		LDFLAGS += -L$(LIBCPP_LIBRARY_DIR) -Wl,-rpath,$(LIBCPP_LIBRARY_DIR) -lc++
 	else
 		ifeq "$(OS)" "Android"
 				# Nothing to do, this is already handled in
@@ -430,7 +433,10 @@
 ifeq ($(or $(USE_LIBSTDCPP), $(USE_LIBCPP), $(USE_SYSTEM_STDLIB)),)
 	ifneq ($(and $(LIBCPP_INCLUDE_DIR), $(LIBCPP_LIBRARY_DIR)),)
 		CXXFLAGS += -nostdlib++ -nostdinc++ -cxx-isystem $(LIBCPP_INCLUDE_DIR)
-		LDFLAGS += -L$(LLVM_LIBS_DIR) -Wl,-rpath,$(LIBCPP_LIBRARY_DIR) -lc++
+		ifneq "$(LIBCPP_INCLUDE_TARGET_DIR)" ""
+				CXXFLAGS += -cxx-isystem $(LIBCPP_INCLUDE_TARGET_DIR)
+		endif
+		LDFLAGS += -L$(LIBCPP_LIBRARY_DIR) -Wl,-rpath,$(LIBCPP_LIBRARY_DIR) -lc++
 	endif
 endif
 
diff --git a/lldb/test/API/lit.cfg.py b/lldb/test/API/lit.cfg.py
--- a/lldb/test/API/lit.cfg.py
+++ b/lldb/test/API/lit.cfg.py
@@ -173,9 +173,11 @@
 # If we have a just-built libcxx, prefer it over the system one.
 if is_configured('has_libcxx') and config.has_libcxx:
   if platform.system() != 'Windows':
-    if is_configured('llvm_include_dir') and is_configured('llvm_libs_dir'):
-      dotest_cmd += ['--libcxx-include-dir', os.path.join(config.llvm_include_dir, 'c++', 'v1')]
-      dotest_cmd += ['--libcxx-library-dir', config.llvm_libs_dir]
+    if is_configured('libcxx_include_dir') and is_configured('libcxx_libs_dir'):
+      dotest_cmd += ['--libcxx-include-dir', config.libcxx_include_dir]
+      if is_configured('libcxx_include_target_dir'):
+        dotest_cmd += ['--libcxx-include-target-dir', config.libcxx_include_target_dir]
+      dotest_cmd += ['--libcxx-library-dir', config.libcxx_libs_dir]
 
 # Forward ASan-specific environment variables to tests, as a test may load an
 # ASan-ified dylib.
diff --git a/lldb/test/API/lit.site.cfg.py.in b/lldb/test/API/lit.site.cfg.py.in
--- a/lldb/test/API/lit.site.cfg.py.in
+++ b/lldb/test/API/lit.site.cfg.py.in
@@ -32,6 +32,9 @@
 config.test_compiler = lit_config.substitute('@LLDB_TEST_COMPILER@')
 config.dsymutil = lit_config.substitute('@LLDB_TEST_DSYMUTIL@')
 config.has_libcxx = @LLDB_HAS_LIBCXX@
+config.libcxx_libs_dir = "@LIBCXX_LIBRARY_DIR@"
+config.libcxx_include_dir = "@LIBCXX_GENERATED_INCLUDE_DIR@"
+config.libcxx_include_target_dir = "@LIBCXX_GENERATED_INCLUDE_TARGET_DIR@"
 # The API tests use their own module caches.
 config.lldb_module_cache = os.path.join("@LLDB_TEST_MODULE_CACHE_LLDB@", "lldb-api")
 config.clang_module_cache = os.path.join("@LLDB_TEST_MODULE_CACHE_CLANG@", "lldb-api")
diff --git a/lldb/test/CMakeLists.txt b/lldb/test/CMakeLists.txt
--- a/lldb/test/CMakeLists.txt
+++ b/lldb/test/CMakeLists.txt
@@ -97,6 +97,14 @@
 
   if (TARGET libcxx OR ("libcxx" IN_LIST LLVM_ENABLE_RUNTIMES))
     set(LLDB_HAS_LIBCXX ON)
+    if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND NOT APPLE)
+      set(LIBCXX_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR}/${LLVM_DEFAULT_TARGET_TRIPLE})
+      set(LIBCXX_GENERATED_INCLUDE_DIR "${LLVM_BINARY_DIR}/include/c++/v1")
+      set(LIBCXX_GENERATED_INCLUDE_TARGET_DIR "${LLVM_BINARY_DIR}/include/${LLVM_DEFAULT_TARGET_TRIPLE}/c++/v1")
+    else()
+      set(LIBCXX_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib${LIBCXX_LIBDIR_SUFFIX})
+      set(LIBCXX_GENERATED_INCLUDE_DIR "${CMAKE_BINARY_DIR}/include/c++/v1")
+    endif()
     add_lldb_test_dependency(cxx)
   endif()
 
diff --git a/lldb/utils/lldb-dotest/CMakeLists.txt b/lldb/utils/lldb-dotest/CMakeLists.txt
--- a/lldb/utils/lldb-dotest/CMakeLists.txt
+++ b/lldb/utils/lldb-dotest/CMakeLists.txt
@@ -9,8 +9,21 @@
 
 llvm_canonicalize_cmake_booleans(
   LLDB_BUILD_INTEL_PT
+  LLDB_HAS_LIBCXX
 )
 
+if ("libcxx" IN_LIST LLVM_ENABLE_RUNTIMES)
+  set(LLDB_HAS_LIBCXX ON)
+  if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND NOT APPLE)
+    set(LIBCXX_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR}/${LLVM_DEFAULT_TARGET_TRIPLE})
+    set(LIBCXX_GENERATED_INCLUDE_DIR "${LLVM_BINARY_DIR}/include/c++/v1")
+    set(LIBCXX_GENERATED_INCLUDE_TARGET_DIR "${LLVM_BINARY_DIR}/include/${LLVM_DEFAULT_TARGET_TRIPLE}/c++/v1")
+  else()
+    set(LIBCXX_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib${LIBCXX_LIBDIR_SUFFIX})
+    set(LIBCXX_GENERATED_INCLUDE_DIR "${CMAKE_BINARY_DIR}/include/c++/v1")
+  endif()
+endif()
+
 set(LLVM_TOOLS_DIR "${LLVM_TOOLS_BINARY_DIR}")
 set(vars
   LLDB_TEST_COMMON_ARGS
@@ -23,8 +36,13 @@
   LLDB_TEST_DSYMUTIL
   LLDB_LIBS_DIR
   LLVM_TOOLS_DIR
+  LIBCXX_LIBRARY_DIR
+  LIBCXX_GENERATED_INCLUDE_DIR
+  LIBCXX_GENERATED_INCLUDE_TARGET_DIR
   )
 
+llvm_canonicalize_cmake_booleans(LLDB_HAS_LIBCXX)
+
 # Generate lldb-dotest Python driver script for each build mode.
 if(LLDB_BUILT_STANDALONE)
   set(config_types ".")
diff --git a/lldb/utils/lldb-dotest/lldb-dotest.in b/lldb/utils/lldb-dotest/lldb-dotest.in
--- a/lldb/utils/lldb-dotest/lldb-dotest.in
+++ b/lldb/utils/lldb-dotest/lldb-dotest.in
@@ -13,6 +13,10 @@
 lldb_framework_dir = "@LLDB_FRAMEWORK_DIR_CONFIGURED@"
 lldb_libs_dir = "@LLDB_LIBS_DIR_CONFIGURED@"
 llvm_tools_dir = "@LLVM_TOOLS_DIR_CONFIGURED@"
+has_libcxx = @LLDB_HAS_LIBCXX@
+libcxx_libs_dir = "@LIBCXX_LIBRARY_DIR@"
+libcxx_include_dir = "@LIBCXX_GENERATED_INCLUDE_DIR@"
+libcxx_include_target_dir = "@LIBCXX_GENERATED_INCLUDE_TARGET_DIR@"
 
 if __name__ == '__main__':
     wrapper_args = sys.argv[1:]
@@ -31,6 +35,11 @@
     cmd.extend(['--dsymutil', dsymutil])
     cmd.extend(['--lldb-libs-dir', lldb_libs_dir])
     cmd.extend(['--llvm-tools-dir', llvm_tools_dir])
+    if has_libcxx:
+        cmd.extend(['--libcxx-include-dir', libcxx_include_dir])
+        if libcxx_include_target_dir:
+            cmd.extend(['--libcxx-include-target-dir', libcxx_include_target_dir])
+        cmd.extend(['--libcxx-library-dir', libcxx_libs_dir])
     if lldb_framework_dir:
         cmd.extend(['--framework', lldb_framework_dir])
     if lldb_build_intel_pt == "1":