diff --git a/libcxx/test/configs/libcxx-trunk-shared.cfg.in b/libcxx/test/configs/libcxx-trunk-shared.cfg.in
--- a/libcxx/test/configs/libcxx-trunk-shared.cfg.in
+++ b/libcxx/test/configs/libcxx-trunk-shared.cfg.in
@@ -7,6 +7,9 @@
 COMPILER = "@CMAKE_CXX_COMPILER@"
 EXEC_ROOT = "@LIBCXX_BINARY_DIR@"
 CMAKE_OSX_SYSROOT = "@CMAKE_OSX_SYSROOT@"
+INCLUDE_DIR = "@LIBCXX_INSTALL_INCLUDE_DIR@"
+INCLUDE_TARGET_DIR = "@LIBCXX_INSTALL_INCLUDE_TARGET_DIR@"
+LIBRARY_DIR = "@LIBCXX_INSTALL_LIBRARY_DIR@"
 
 import os
 import pipes
@@ -32,13 +35,14 @@
     '-isysroot {}'.format(CMAKE_OSX_SYSROOT) if CMAKE_OSX_SYSROOT else ''
 ))
 config.substitutions.append(('%{compile_flags}',
-    '-nostdinc++ -isystem {} -I {}'.format(
-        os.path.join(INSTALL_ROOT, 'include', 'c++', 'v1'),
+    '-nostdinc++ -isystem {} -isystem {} -I {}'.format(
+        os.path.join(INSTALL_ROOT, INCLUDE_DIR),
+        os.path.join(INSTALL_ROOT, INCLUDE_TARGET_DIR),
         os.path.join(LIBCXX_ROOT, 'test', 'support'))
 ))
 config.substitutions.append(('%{link_flags}',
     '-nostdlib++ -L {0} -lc++ -Wl,-rpath,{0} -pthread'.format(
-        os.path.join(INSTALL_ROOT, 'lib'))
+        os.path.join(INSTALL_ROOT, LIBRARY_DIR))
 ))
 config.substitutions.append(('%{exec}',
     '{} {} --execdir %T -- '.format(
diff --git a/libcxx/test/configs/libcxx-trunk-static.cfg.in b/libcxx/test/configs/libcxx-trunk-static.cfg.in
--- a/libcxx/test/configs/libcxx-trunk-static.cfg.in
+++ b/libcxx/test/configs/libcxx-trunk-static.cfg.in
@@ -7,6 +7,9 @@
 COMPILER = "@CMAKE_CXX_COMPILER@"
 EXEC_ROOT = "@LIBCXX_BINARY_DIR@"
 CMAKE_OSX_SYSROOT = "@CMAKE_OSX_SYSROOT@"
+INCLUDE_DIR = "@LIBCXX_INSTALL_INCLUDE_DIR@"
+INCLUDE_TARGET_DIR = "@LIBCXX_INSTALL_INCLUDE_TARGET_DIR@"
+LIBRARY_DIR = "@LIBCXX_INSTALL_LIBRARY_DIR@"
 
 import os
 import pipes
@@ -32,13 +35,14 @@
     '-isysroot {}'.format(CMAKE_OSX_SYSROOT) if CMAKE_OSX_SYSROOT else ''
 ))
 config.substitutions.append(('%{compile_flags}',
-    '-nostdinc++ -isystem {} -I {}'.format(
-        os.path.join(INSTALL_ROOT, 'include', 'c++', 'v1'),
+    '-nostdinc++ -isystem {} -isystem {} -I {}'.format(
+        os.path.join(INSTALL_ROOT, INCLUDE_DIR),
+        os.path.join(INSTALL_ROOT, INCLUDE_TARGET_DIR),
         os.path.join(LIBCXX_ROOT, 'test', 'support'))
 ))
 config.substitutions.append(('%{link_flags}',
     '-nostdlib++ -L {} -lc++ -lc++abi -pthread'.format(
-        os.path.join(INSTALL_ROOT, 'lib'))
+        os.path.join(INSTALL_ROOT, LIBRARY_DIR))
 ))
 config.substitutions.append(('%{exec}',
     '{} {} --execdir %T -- '.format(
diff --git a/libcxx/utils/ci/run-buildbot b/libcxx/utils/ci/run-buildbot
--- a/libcxx/utils/ci/run-buildbot
+++ b/libcxx/utils/ci/run-buildbot
@@ -81,6 +81,7 @@
           -B "${BUILD_DIR}" \
           -GNinja -DCMAKE_MAKE_PROGRAM="${NINJA}" \
           -DCMAKE_BUILD_TYPE=RelWithDebInfo \
+          -DCMAKE_CXX_COMPILER=$HOME/Stable/bin/clang++ -DCMAKE_C_COMPILER=$HOME/Stable/bin/clang \
           -DCMAKE_INSTALL_PREFIX="${INSTALL_DIR}" \
           -DLLVM_LIT_ARGS="-sv --show-unsupported --xunit-xml-output test-results.xml" \
           "${@}"